LIT-001-00 – OPERATION MAINTENANCE SERVICE MANUAL 600-8,000 LBS. AXLE CAPACITY – DEXTER

SEOCONTENT-START

OPERATION MAINTENANCE
SERVICE MANUAL
600-8,000 LBS. AXLE CAPACITY
l ::J®
DEXTER
Introduction
This manual is designed to provide information for you to understand, use, maintain, and
service your trailer running gear system. Your axles are manufactured by Dexter. Since
1960, Dexter’s experience in the design, testing, and manufacturing of trailer axles has
resulted in the most complete product line in the industry. The Dexter running gear system
consists of axles, suspensions, and braking systems which are engineered to provide you
the finest towing and stopping performance available today.
Two Dexter philosophies are at work to provide you the best product available and have
enabled us to maintain our position of leadership. First, we operate on the theory that
“there is always a better way” for a product to operate, to be manufactured, and/or to be
serviced. We are constantly striving to find that better way.
Secondly, we maintain the highest quality control standards in the industry and adhere
to ISO 9001:2015. Dexter has operated with detailed documented processes and
procedures long before completing ISO Certification, continually placing quality and
customer service as the focus. This ensures that critical components including axle
beams, hubs, drums, spindles, and braking systems are manufactured to the highest
quality standards so that we can provide our customers with dependable products, the
most comprehensive product offering and reliable, consistent customer service.
Trusting is hard. Knowing who to trust even harder. Through vertical integration we engineer,
design, manufacture and test virtually every part in-house to ensure superior quality trailer
running gear. We fuss over details, so you don’t have to. Trust Dexter.
Visit us online at www.dexteraxle.com.

~
Introduction
Important Safety Notice ……………………………………………………………………………………….. .4
Getting Started – Setup and Adjustment …………………………………………………………………… 4
Braking Systems – Electric
Electric Brakes …………………………………………………………………………………………………….. 5
Features …………………………………………………………………………………………………………….. 6
Parking Brake Option ……………………………………………………………………………………. 6
Self Adjusting Feature ………………………………………………………………………………….. 6
Brake Controllers …………………………………………………………………………………………. 7
Typical Trailer Wiring ……………………………………………………………………………………. 10
How to Use Your Electric Brakes Properly ……………………………………………………….. 11
Trailer Wire Size Chart …………………………………………………………………………………. 11
SynchronizingYourTrailer Brakes ………………………………………………………………….. 12
General Maintenance Electric Brakes …………………………………………………………………….. 13
Brake Adjustment. ……………………………………………………………………………………… 13
Brake Cleaning and lnspection …………………………………………………………………….. 14
Brake Lubrication ………………………………………………………………………………………. 14
Magnets …………………………………………………………………………………………………………… 15
Shoes and Linings ……………………………………………………………………………………………… 16
Introduction to Troubleshooting …………………………………………………………………………….. 17
Troubleshooting …………………………………………………………………………………………………. 17
Troubleshooting Chart- Electric ……………………………………………………………………. 18
How to Measure Voltage ……………………………………………………………………………… 20
How to Measure Amperage ………………………………………………………………………….. 20
Magnet Amperes Chart ……………………………………………………………………………….. 21
Braking Systems – Hydraulic
Hydraulic Brakes ………………………………………………………………………………………………… 23
Hydraulic Drum Brake Operation …………………………………………………………………………… 24
Duo-Servo ………………………………………………………………………………………………… 24
Uni-Servo …………………………………………………………………………………………………. 24
Self-Adjusting Mechanism for 12 1/ 4″ Brakes ……………………………………………….. 25
Hydraulic Parking Brake Option ……………………………………………………………………. 25
Hydraulic Disc Brakes …………………………………………………………………………………. 27
Actuation Systems ……………………………………………………………………………………………… 28
Electrical Schematic …………………………………………………………………………………… 28
Troubleshooting Guide ………………………………………………………………………………… 29
General Maintenance – Hydraulic Brakes ………………………………………………………………… 31
Drum Brake Adjustment – Manual …………………………………………………………………. 31
Wheel Cylinders ………………………………………………………………………………………… 32
Brake Lines ………………………………………………………………………………………………. 32
Shoes and Linings ……………………………………………………………………………………… 32
Hardware …………………………………………………………………………………………………. 33
Instructions for Brake Caliper Kit – 3.5K Disc Brakes ………………………………………… 33
Instructions for Brake Rotor Kit – 3.5K Disc Brakes ………………………………………….. 34
Instructions for Brake Rotor Kit – 6K or BK Disc Brakes …………………………………….. 36
Instructions for Brake Hub/Rotor Kit- 7K Disc Brakes ……………………………………… 37
Instructions for Brake Pad Kit – 6K, 7K or BK Disc Brakes …………………………………. 39
Instructions for Brake Caliper Kit- 6K, 7K or BK Disc Brakes ……………………………. .42
Introduction to Troubleshooting ……………………………………………………………………………. .45
Troubleshooting Chart – Hydraulic …………………………………………………………………. 46
Hubs/Drums/Bearings
Hubs/Drums/Bearings ……………………………………………………………………………….. 48
Hub Removal – Standard Bearings ………………………………………………………………… 49
Brake Drum lnspection ……………………………………………………………………………….. 49
Bearing Inspection …………………………………………………………………………………….. 50
Bearing Lubrication – Grease ………………………………………………………………………. 52
Bearing Lubrication – Oil ……………………………………………………………………………… 52
Recommended Wheel Bearing Lubrication Specifications …………………………………. 53
Seal Inspection and Replacement ………………………………………………………………… 55
Bearing Adjustment and Hub Replacement …………………………………………………….. 56
Typical E-Z Lube’ After Spring 2002 ………………………………………………………………. 57
E-Z Lube” Lubrication …………………………………………………………………………………. 57
Nev-R-Lube’ Drums/Bearings ………………………………………………………………………………. 59
Drum Removal ………………………………………………………………………………………….. 60
Bearing Inspection …………………………………………………………………………………….. 60
Nev-R-Lube’ Bearing End Play Inspection ………………………………………………………. 61
Bearing Replacement and Drum lnstallation …………………………………………………… 62
Axle Installation
Axle & Suspension Installation …………………………………………………………………………….. 64
Suspensions
Suspension Systems ………………………………………………………………………………………….. 65
Double Eye Leaf Springs ……………………………………………………………………………… 65
Grease Lubricated Suspension Bushings ……………………………………………………….. 66
Slipper Leaf Springs …………………………………………………………………………………… 66
Inspection and Replacement. ………………………………………………………………………. 67
Suspension Fastener Torque Values ………………………………………………………………. 67
Torflex• Suspension ……………………………………………………………………………………. 69
Airflex· Suspension ……………………………………………………………………………………. 70
Wheels and Tires
Wheels …………………………………………………………………………………………………………….. 72
Wheel Selection ………………………………………………………………………………………… 72
Torque Requirements ………………………………………………………………………………….. 73
Wheel Torque Requirements ………………………………………………………………………… 7 4
Maximum Wheel FastenerTorque ………………………………………………………………….. 75
Tires ………………………………………………………………………………………………………………… 76
Tire Wear Diagnostic Chart …………………………………………………………………………… 77
Replacement Parts/Kits
Magnet Replacement Kits and Brake Nut Torque ……………………………………………… 78
Seal Replacement Reference ………………………………………………………………………. 78
Brake Shoe Replacement Kits ……………………………………………………………………… 79
Bearing Replacement Chart …………………………………………………………………………. 80
Storage
Storage Preparation ……………………………………………………………………………………………. 81
After Prolonged Storage – Inspection Procedures ……………………………………………………… 82
Trip Preparation Checklist ……………………………………………………………………………………. 83
Maintenance Schedule
Maintenance Schedule Chart ……………………………………………………………………………….. 84
Warranty
Limited Warranty ………………………………………………………………………………………………… 85
Axle Identification
Axle Identification ………………………………………………………………………………………………. 88
Video Gallery
Dexter Video Gallery …………………………………………………………………………………………… 90

Important Safety Notice
Appropriate service methods and repair procedures are essential for the safe,
reliable operation of all running gear as well as the personal safety of the
individual doing the work. This manual provides general directions for performing
service and repair work with tested, effective techniques. Following these
guidelines will help assure reliability.
There are numerous variations in procedures, techniques, tools, parts for
servicing axles, as well as in the skill of the individual doing the work. This
manual cannot possibly anticipate all such variations and provide advice or
cautions as to each. Anyone who departs from the instructions provided in this
manual must first establish that they neither compromise their personal safety
nor the vehicle integrity by their choice of methods, tools, or parts.
Refer to your vehicle manufacturer’s owners manual for additional procedures,
techniques, and warnings prior to performing any maintenance or repairs.
&CAUTION
This Is the safety alert symbol. It Is used to alert you to potential
injury hazards. Obey all safety messages that follow this symbol to
avoid possible injury or death.
Getting Started – Setup and Adjustment
For proper performance, all new axles should have the following checked at the
specified intervals:
Wheel NutTorque: at 10, 25, and 50 miles
Brake Adjustment: at 200 and 3,000 miles
Tire pressure: to manufacturer’s requirements
Brake synchronization: set brake controller per controller manufacturer’s
directions
-4-
Electric Brakes
The electric brakes on your trailer are similar to the drum brakes on your
automobile. The basic difference is that your automotive brakes are actuated
by hydraulic pressure while your electric trailer brakes are actuated by an
electromagnet. With all of the brake components connected into the system, the
brake will operate as follows:
Primary Shoe
Actuating Lever
Front of Brake
Magnet
Adjuster Spring
Shoe Hold
Down Spring
When the electrical current is fed into the system by the controller, it flows
through the electromagnets in the brakes. The high capacity electromagnets are
energized and are attracted to the rotating armature surface of the drums which
moves the actuating levers in the direction that the drums are turning.
The resulting force causes the actuating cam block at the shoe end of the lever
to push the primary shoe out against the inside surface of the brake drum. The
force generated by the primary shoe acting through the adjuster moves the
secondary shoe out into contact with the brake drum.
Increasing the current flow to the electromagnet causes the magnet to grip
the armature surface of the brake drum more firmly. This results in increasing
the pressure against the shoes and brake drums until the desired stop is
accomplished.
-5-

Features
Electrically actuated brakes have several advantages over other brake actuation
systems.
1. They can be manually adjusted at the controller to provide the correct
braking capability for varying road and load conditions.
2. They can be modulated to provide more or less braking force, thus
easing the brake load on the towing vehicle.
3. They have very little lag time from the moment the tow vehicle’s brakes
are actuated until the trailer brakes are actuated.
4. In an emergency situation, they can provide some braking independent
of the tow vehicle.
Parking Brake Option
(Nat available an all sizes)
Dexter electric brakes with parking brake option are mechanically operated by
a cable. Cable force applied to the parking lever creates a torque through the
pivot pin and cam assembly. Torque transferred to the parking cam results in a
spreading force between the primary and secondary shoes. The shoes, in turn,
move towards the drum until contact is made. Friction generated between the
drum and lining contact surface keeps the drum from rotating under normal
loading conditions.
Self Adjusting Feature
(Nat available an all sizes)
Dexter electric brakes may be equipped with a forward self-adjust feature.
This will allow the brakes to adjust on both forward and reverse stops. Brake
adjustment occurs when lining wear results in enough gap between the shoes
and the brake drum surface. This added clearance will allow the adjuster
mechanism to rotate the screw assembly at the bottom of the brake. That action
expands the distance between the shoes and thus closes the gap to the drum
surface.
-6-
Brake Controllers
Electric brake controllers provide power to the magnets to actuate the trailer
brakes. Dexter offers a state-of-the-art inertial controller called the Predator
DX2°. This controller features a patented accelerometer design which senses
the deceleration of the towing vehicle and sends a proportional voltage to the
electric trailer brakes. Other features include a visual gain setting for quick and
easy adjustment and a digital LED display to show the voltage output. A manual
override sends full voltage to the trailer brakes, regardless of gain setting,
for emergency conditions and also illuminates the brake lights to warn of an
impending stop.
Most electric brake controllers provide a modulation function that varies the
current to the electric brakes with the pressure on the brake pedal or amount of
deceleration of the tow vehicle. Electronic or timing controllers do not provide
proportional modulation. These controllers tend to be inexpensive but not the
best choice for optimum braking. It is important that your brake controller
provide approximately 2 volts to the braking system when the brake pedal is
first depressed and gradually increases the voltage to 12 volts as brake pedal
pressure is increased. If the controller “jumps” immediately to a high voltage
output, even during a gradual stop, then the electric brakes will always be fully
energized and will result in harsh brakes and potential wheel lockup.
-7-

Dexter Electric Brakes
Wired in parallel.
Breakaway Battery
Provides power to actuate
trailer brakes in the event of
trailer breakaway.
Breakaway Switch
Switches battery power
to brakes if
breakaway occurs.
-8-
Controller
Electric brake controller
provides power to the
magnets to actuate the
trailer brakes.
Battery
Connect controller directly.
Connector
Used to connect and disconnect
trailer and tow vehicle.
(Always ground trailer brakes
through connector).
-9-

Typical Trailer Wiring
Double
FIiament
Bulb
License Tall &
Running Lights ,.,,.,.,,.
Terminal#3
Electric Brake
Terminal #2 Blue
Yellow
White
~ Orange
ID
I
Auxlllary Circuit’
Tenninal #7 1
~~!°J:.i!,!:’9&hlTUrn Signal 1
Trailer
7-Clrcult Receptacle
ery
Tail Ugh arge
Towing Vehicle
9-Circuit Receptacle
&
rn
Groun Clearance &
Stop&
RH Turn
Tail Lights
Battery
kes
Brake ….,__,’—‘” Charge
Auxiliary
View Looking into Tow Vehicle Receptacle
-10-
How to Use Your Electric Brakes Properly
Your trailer brakes are designed to work in synchronization with your tow vehicle
brakes. Never use your tow vehicle or trailer brakes alone to stop the combined
load.
Your brake controller must be set up according to the manufacturer’s
recommendations to ensure proper synchronization between the tow vehicle and
the trailer. Additionally, you may have to make small adjustments occasionally to
accommodate changing loads and driving conditions.
Proper synchronization of tow vehicle to trailer braking can only be
accomplished by road testing. Brake lockup, grabbiness, or harshness is quite
often due to the lack of synchronization between the tow vehicle and the trailer
being towed, too high of a threshold voltage (over 2 volts), or under adjusted
brakes.
Before any synchronization adjustments are made, your trailer brakes should
be burnished-in by applying the brakes 20-30 times with approximately a 20
m.p.h. decrease in speed, e.g. 40 m.p.h. to 20 m.p.h. Allow ample time for
brakes to cool between application. This allows the brake shoes and magnets to
slightly “wear-in” to the drum surfaces.
Trailer Wire Size Chart
Number
of Brakes
2
4
4
6
6
Recommended
Hitch-to-Axle Distance Minimum Hookup Wire
in Feet Size (Copper)
12AWG
Under30 12AWG
30-50 10AWG
Under30 10AWG
30-50 8AWG

Synchronizing Your Trailer Brakes
To ensure safe brake performance and synchronization, read the brake controller
manufacturer’s instructions completely before attempting any synchronization
procedure.
&CAUTION
Before road testing, make sure the area Is clear of vehicular and
pedestrian traffic. Failure to brake safely could result In an accident
and personal Injury to yourself and/or others.
Make several hard stops from 20 m.p.h. on a dry paved road free of sand
and gravel. If the trailer brakes lock and slide, decrease the gain setting on
the controller. If they do not slide, slightly increase the gain setting. Adjust the
controller just to the point of impending brake lockup and wheel skid.
Note: Not all trailer brakes are capable of wheel lockup. Loading conditions,
brake type, wheel and tire size can all affect whether a brake can lock. It is not
generally considered desirable to lock up the brakes and slide the tires. This
can cause unwanted flat spotting of the tires and could also result in a loss of
control.
If the controller is applying the trailer brakes before the tow vehicle brakes, then
the controller adjustments should be made so the trailer brakes come on in
synchronization with the tow vehicle brakes. For proper braking performance,
it is recommended that the controller be adjusted to allow the trailer brakes
to come on just slightly ahead of the tow vehicle brakes. When proper
synchronization is achieved there will be no sensation of the trailer “jerking” or
“pushing” the tow vehicle during braking.
-12-
General Maintenance – Electric Brakes
Brake Adjustment
Dexter electric brakes that have a self adjusting feature require no manual
adjustment. Brakes not equipped with this feature can be adjusted by using the
following procedure:
Brakes should be adjusted (1) after the first 200 miles of operation when the
brake shoes and drums have “seated;’ (2) at 3,000 mile intervals, (3) or as
use and performance requires. The brakes should be adjusted in the following
manner:
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturer’s recommendations for lifting and supporting the
unit. Make sure the wheel and drum rotates freely.
&CAUTION
Do not 11ft or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless It Is properly supported on
Jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. If equipped, remove the adjusting hole cover, if present, from the
adjusting slot on the bottom of the brake backing plate.
3. With a screwdriver or standard adjusting tool, rotate the star wheel of the
adjuster assembly to expand the brake shoes. Adjust the brake shoes
out until the pressure of the linings against the drum makes the wheel
very difficult to turn.
Note: For drop spindle axles, a modified adjusting tool may be
necessary.
4. Then rotate the star wheel in the opposite direction until the wheel turns
freely with a slight lining drag.
5. Replace the adjusting hole cover, if available, and lower the wheel to the
ground.
6. Repeat the above procedure on all brakes. For best results, the brakes
should all be set at the same clearance.
-13-

Brake Cleaning and Inspection
Your trailer brakes must be inspected and serviced immediately if a loss of
performance is indicated. With normal use, servicing at one year intervals
is usually adequate. With increased usage, this work should be done more
frequently as required. Magnets and shoes must be changed when they become
excessively worn or scored, a condition which can reduce vehicle braking.
Clean the backing plate, magnet arm, magnet, and brake shoes. Make certain
that all the parts removed are replaced in the same brake and drum assembly.
Inspect for any loose or worn parts, stretched or deformed springs and replace
as necessary.
&CAUTION
POTENTIAL ASBESTOS DUST HAZARD!
Some older brake linings may contain asbestos dust, which has been
linked to serious or fatal illnesses. Certain precautions need to be
taken when servicing brakes:
1. Avoid creating or breathing dust.
2. Avoid machining, filing or grinding the brake linings.
3. Do not use compressed air or dry brushing for cleaning (dust can
be removed with a damp brush).
Brake Lubrication
“C Before reassembling, apply a light film of grease or anti-seize compound on “S the brake anchor pin, the actuating arm bushing and pin, and the areas on the
Cl) backing plate that are in contact with the brake shoes and magnet lever arm.
iii Apply a light film of grease on the actuating block mounted on the actuating
arm.
CAUTION
Do not get grease or oil on the brake linings, drums or magnets.
-14-
Magnets
Your electric brakes are equipped with high quality electromagnets that are
designed to provide the proper input force and friction characteristics. Your
magnets should be inspected and replaced if worn unevenly or abnormally. As
indicated below, a straightedge should be used to check magnet condition. For
best results, the magnet should be flat.
Even if wear is normal as indicated by your straightedge, the magnets should be
replaced if any part of the magnet coil has become visible through the friction
material facing of the magnet. It is also recommended that the drum armature
surface be refaced when replacing magnets (see section on Brake Drum
Inspection). Magnets should also be replaced in pairs – both sides of an axle.
Use only genuine Dexter replacement parts when replacing your magnets.
NORMAL WEAR
-15-
Gaps show ABNORMAL
WEAR (replace magnet}

Shoes and Linings
A simple visual inspection of your brake linings will tell if they are usable.
Replacement is necessary if the lining is worn to 1/16” or less. Shoes
contaminated with grease or oil,
or abnormally scored or gouged
should also be replaced. Hairline
heat cracks are normal in bonded
linings and should not be cause
for concern. When replacement is
necessary, it is important to replace
both shoes on each brake and both
brakes of the same axle. This will
help retain the “balance” of your
brakes.
&CAUTION
POTENTIAL ASBESTOS DUST HAZARD!
Acceptable
Hairline Cracks
Some older brake llnlngs may contain asbestos dust, which has been
llnked to serious or fatal Illnesses. Certain precautions need to be
taken when servicing brakes:
1. Avoid creating or breathing dust.
2. Avoid machining, flllng or grinding the brake llnlngs.
3. Do not use compressed air or dry brushing for cleaning (dust can
be removed with a damp brush).
After replacement of brake shoes and linings, the brakes must be re-burnished
to seat in the new components. This should be done by applying the brakes 20
to 30 times from an initial speed of 40 m.p.h., slowing the vehicle to 20 m.p.h.
Allow ample time for brakes to cool between applications. This procedure allows
the brake shoes to seat in to the drum surface.
-16-
Introduction to Troubleshooting
Proper brake function is critical to the safe operation of any vehicle. If problems
are encountered with your trailer braking system, the following guide can be
used to find the causes and remedies for some of the more common problems.
If you are unsure or unable to resolve the problem, please contact your nearest
repair facility for professional assistance.
Troubleshooting
Most electric brake malfunctions that cannot be corrected by either brake
adjustments or synchronization adjustments, can generally be traced to
electrical system failure. Voltmeters and ammeters are essential tools for proper
troubleshooting of electric brakes.
Mechanical causes are ordinarily obvious, i.e. bent or broken parts, worn out
linings or magnets, seized lever arms or shoes, scored drums, loose parts, etc.
Replace defective parts with genuine Dexter replacements.
Please consult the following troubleshooting charts to determine the causes and
solutions for common problems found in trailer braking systems.
&CAUTION
Best braking performance is achieved with a controller setting that is
just short of wheel lock up or slide. Overly aggressive braking which
results in wheel lock up and sliding, can cause a dangerous loss of
control and result in personal injury or death.
-17-

Troubleshooting
SYMPTOM CAUSES REMEDIES
Open Circuits Find & Correct
No Brakes
Severe
UnderadJustment Adjust Brakes
Faulty Controller Test & Correct
Short Circuits Find & Correct
Grease or OIi on
Magnets or Linings Clean or Replace
Corroded Connections Clean & Correct
Cause of Corrosion
Worn Linings
or Magnets Replace
Scored or Grooved Machine or Replace Brake Drums
Weak Brakes
Improper
Synchronization Correct
Underadjustment Adjust Brakes
Glazed Linings Reburnlsh or Replace
Overloaded Trailer Correct
UnderadJustment Adjust
·u- Syn~~’::rz=:i1on Correct ….. u -CL) Faulty Controller Test & Correct Locking Brakes LLI Loose, Bent or Broken
Brake Components Replace Components
“‘ Out-of-Round Machine or Replace E Brake Drums
CL)
Insufficient Wheel Load Adj~~~ lvs~:;i,:,:s~stor .. ~”‘ Faulty Controller Test & Correct
‘CO Intermittent Brakes Broken Wires Repair or Replace ·C- .=.:: Loose Connections Find & Repair e m Faulty Ground Find & Repair
-18-
Troubleshooting m
;J
SYMPTOM CAUSES REMEDIES -::ii·=- ::::s
~r:;en~:r:or Correct C10.
Incorrect Adjustment Adjust ~ Cl)
Grease or 011 on ….
Linings or Magnets Clean or Replace CD
Brakes Pull to 3 One Side
Broken Wires Find & Repair Cl)
Bad Connections Find & Repelr -‘” Underadjustment Adjust CD
.C.”.). Improper Correct .. Synchronization -· Harsh Brakes C”)
Improper Controller Change
Faulty Controller Test & Correct
Underadjustment Adjust
lack of lubrication lubricate
Noisy Breke
Broken Replace Component Brake Components
Incorrect Brake
Components Correct
Grease or 011 on Clean or Replace Linings or Magnet
Surging Brakes Out.of.Round or Machine or Replace
Cracked Brake Drums
Faulty Controller Test & Correct
Overad)ustment Readjust
Out-of-Round Machine or Replace
Brake Drums
Incorrect Brake Replace
Components
Dragging Brakes Loose, Bent or Broken Replace
Brake Components
Faulty Breakaway
Switch
Repelr or Replace
loose Wheel Adjust Bearing Adjustment
Bent Spindle Replace Axle

How to Measure Voltage
System voltage is measured at the magnets by connecting the voltmeter to the
two magnet lead wires at any brake. This may be accomplished by using a pin
probe inserted through the insulation of the wires. The engine of the towing
vehicle should be running when checking the voltage so that a low battery will
not affect the readings.
Voltage in the system should
begin at O volts and, as the
controller bar is slowly actuated,
should gradually increase to
about 12 volts. If the controller
does not produce this voltage
control, consult your controller
manual.
The threshold voltage of a
controller is the voltage applied
to the brakes when the controller first turns on. Lower threshold voltage will
provide for smoother braking. If the threshold voltage is too high, the brakes may
feel grabby and harsh.
How to Measure Amperage
System amperage is the current flowing in the system when all the magnets are
energized. The amperage will vary in proportion to the voltage. The engine of
u the tow vehicle should be running with the trailer connected when checking the
“..C.., trailer braking system .
i One place to measure system amperage is at the BLUE wire of the controller,
iiJ which is the output to the brakes. The BLUE wire must be disconnected and the
ammeter put in series into the line. System amperage draw should be as noted
en in the following table. Make sure your ammeter has sufficient capacity and note
E polarity to prevent damaging your ammeter.

-20-
Magnet Amperes Chart
Brake Amps/
Size Magnet
7″ X 11/4″ 2.5
10″ X 11/2″ 3.0
10″ X 2 1/4″ 3.0
12″ X 2″ 3.0
12 1/4″ X 2 1/2″ 3.0
12 1/4″ X 3 3/8″ 3.0
Two
Brakes
5.0
6.0
6.0
6.0
6.0
6.0
Four
Brakes
10.0
12.0
12.0
12.0
12.0
12.0
Six
Brakes
15.0
18.0
18.0
18.0
18.0
18.0
Magnet
Ohms
3.9
3.2
3.2
3.2
3.2
3.2
If a resistor is used in the brake system, it must be set at zero or bypassed
completely to obtain the maximum amperage reading. Individual amperage
draw can be measured by
inserting the ammeter in the line
at the magnet you want to check.
Disconnect one of the magnet
lead wire connectors and attach
the ammeter between the two
wires. Make sure that the wires
are properly reconnected and ~ 1
sealed after testing is completed. o ~~c:=::::…-
The most common electrical !..=-::::==:
problem is low or no voltage and amperage at the brakes. Common causes of
this condition are:
1. Poor electrical connections
2. Open circuits
3. Insufficient wire size
4. Broken wires
5. Blown fuses (fusing of brakes is not recommended)
6. Improperly functioning controllers or resistors
Another common electrical problem is shorted or partially shorted circuits
(indicated by abnormally high system amperage). Possible causes are:
1. Shorted magnet coils
2. Defective controllers
3. Bare wires contacting a grounded object
-21-

Finding the cause of a short circuit in the system is done by isolating one
section at a time. If the high amperage reading drops to zero by unplugging the
trailer, then the short is in the trailer. If the amperage reading remains high with
all the brake magnets disconnected, the short is in the trailer wiring.
All electrical troubleshooting procedures should start at the controller.
Most complaints regarding brake harshness or malfunction are traceable
to improperly adjusted or non-functioning controllers. See your controller
manufacturer’s data for proper adjustment and testing procedures. For best
results, all the connection points in the brake wiring should be sealed to prevent
corrosion. Loose or corroded connectors will cause an increase in resistance
which reduces the voltage available for the brake magnets.
-22-
Hydraulic Brakes
Dexter offers several varieties of hydraulic trailer brakes. Your vehicle may be
equipped with drum brakes or disc brakes.
The hydraulic brakes on your trailer are much like those on your automobile
or light truck. The hydraulic fluid from a master cylinder or actuation system is
used to actuate the wheel cylinder which, in turn, applies force against the brake
shoes and drum. The main difference between automotive hydraulic brakes and
hydraulic trailer brakes is the trailers’ actuation system. These systems respond
to the braking signal from the tow vehicle and supply the required brake fluid
volume and pressure to the trailer brakes.
In the following pages you will find a more detailed description of the hydraulic
brakes and actuation system used on your trailer.
CAUTION
The maximum operating pressure for Dexter brakes:
7″ diameter drum brakes
maximum operating pressure is 750 psi
10” diameter and larger drum brakes
maximum operating pressure is 1,000 psi
Hydraulic disc brakes (all sizes)
maximum operating pressure is 1,600 psi
-23-

Hydraulic Drum Brake Operation
Duo-Servo
The duo-servo brake uses a dual piston wheel cylinder to apply the brakes. This
type of brake is typically used in an electric/hydraulic, vacuum/hydraulic, or air/
hydraulic system. A description of operation of this brake is as follows:
When the brakes are applied, the double-acting wheel cylinder moves the
primary and secondary shoes towards the drum. The frictional force between
the brake drum and lining attempts to turn the primary shoe into the secondary
shoe. The secondary shoe is forced onto the anchor pin and from this point, the
secondary and primary
shoes attempt to “wrap
around”. In essence,
the brake has utilized
frictional force to help
the applying force on
both shoes.
If the brakes are
applied while the
vehicle is backing, the
shoes rotate in the
direction of the drum
rotation. This causes
the secondary shoe
Backing
Plate
Anchor Post
Actuating Pin
Adjuster Assembly
to leave the anchor and causes the primary shoe to move against the anchor.
Action of the brake is the same in reverse as forward.
Uni-Servo
This type of hydraulic brake utilizes a single acting cylinder. Upon actuation, the
primary shoe is pressed against the brake drum, which causes the shoe to move
in the direction of rotation. This movement in turn actuates the secondary shoe
through the adjuster assembly. Braking in reverse is significantly less effective
than in the forward direction.
-24-
Another variation is called a “free backing” brake which is commonly used
on trailers with a surge hitch system. When backing with a surge brake hitch,
normal brakes are applied through the surge mechanism and if there is more
brake force on the trailer than the tow vehicle can override, no backing is
possible. The free
backing brake was
developed to allow
backing in this
application. This brake
Anchor Post
has a primary shoe on Backing
a pivot which allows Plate
normal application in
the forward direction,
but allows the primary
shoe to rotate away
from the drum surface
when backing.
Self Adjusting Mechanism
for 12¼” Hydraulic Brakes
Actuating Pin
Adjuster Assembly
Forward self-adjust hydraulic brakes were introduced in March of 1997. This
feature adjusts the brakes on both forward and reverse stops. Brake adjustment
occurs only when lining wear results in enough gap between the shoes and
the drum surface. This added clearance will allow the adjuster mechanism to
rotate the screw assembly at the bottom of the brake. That action expands the
distance between the shoes and thus closes the gap to the drum surface.
Hydraulic Parking Brake Option
(Nat available an all sizes)
The parking feature on Dexter hydraulic brakes is cable operated. On the 10″
and 12″ brakes, the parking cable body is mounted to the brake backing plate.
The cable end is attached to the internal parking brake lever to actuate the
brake. On Dexter 12 1/4″ brakes manufactured before February of 2002, the
parking cable body mounts to a support plate which is attached to the brake
mounting flange. The cable end is routed through the dust shield and the
brake spider, to attach to the internal parking brake lever. For 12 1/4″ brakes
produced after February of 2002, a short cable is installed directly into the
backing plate to provide a convenient means for the trailer manufacturer to
attach an appropriate operating system.
-25-

The internal parking brake lever of 10″ and 12″ Dexter brakes, which is mounted
to the secondary shoe, transfers applied cable force through a parking strut
which is attached to the primary shoe. This transferred load generates a
spreading force between the primary and secondary shoes. The shoes move
toward the drum until contact is made. Friction generated between the drum
and lining contact surface results in parking brake capability.
The internal parking brake lever of Dexter 12 1/ 4″ brakes transfers the applied
cable force through a cam mechanism. The cam mechanism generates a
spreading force between the primary and secondary shoes. The shoes move
toward the drum until contact is made. Friction generated between the drum
and lining contact surface results in parking brake capability.
Park Lever
Park Cable
-26-
Hydraulic Disc Brakes
Dexter manufactures two types of disc brakes, the floating caliper and the
fixed caliper brake. With both styles, the disc brake uses friction pads astride a
ventilated rotor which is attached to the wheel hub. When the brake is actuated,
the pads are pressed against the sides of the rotor causing drag to slow the
rotating disc. This action converts the kinetic energy (motion) into heat. The heat
is dissipated rapidly by the ventilated disc.
The floating caliper brake uses piston(s) situated on one side of the brake
rotor. Hydraulic fluid pressure pushes against the piston(s) to apply the inboard
brake pad. As the inboard pad exerts force against the rotating rotor surface,
the caliper moves laterally towards the trailer frame and in turn applies an
equivalent force to the outboard brake pad against the rotor surface. As the
lining material wears, the caliper will automatically maintain the proper lining to
rotor clearance. The floating caliper design is used on Dexter 3,500 lb., 10,000
lb. and 12,000 lb. axle models.
The fixed caliper method uses pistons situated on both sides of the rotor. During
actuation, hydraulic pressure pushes against the pistons to apply the inboard
and outboard brake pads equally to decelerate the rotating rotor. The caliper is
fixed and stays stationary during brake
actuation and brake adjustment. Brake
pad to rotor clearance is maintained
as lining wear occurs via the brake
piston and internal caliper seal. The
fixed caliper design is used on the
Dexter 6,000, 7,000 and 8,000 lb. axle
models.
Disc brake effectiveness is the same
going either in a forward or reverse
direction. All Dexter disc brakes should
be actuated with a braking system that
is capable of providing a maximum
hydraulic pressure of 1,600 psi.
-27-

Actuation Systems
To effectively operate your hydraulic trailer brakes we recommend the Dexter
electrically controlled hydraulic brake actuation device (also referred to as E/H
brake actuator), controlled by the Predator DX2° electronic brake controller.
These high performance hydraulic power modules will supply pressurized brake
fluid to your trailer brakes in proportion to the amount of braking effort called for
by the towing vehicles’ deceleration rate.
CAUTION
It is the responsibility of the end user to ensure that their in-cab
electronic controller is compatible with the Dexter E/H brake
actuator. Dexter attempts to provide compatibility with most
controllers available, but is unable to anticipate design changes that
might be introduced by the various controller manufacturers.
The E/H 1000 will supply 1,000 psi for your drum brakes and the E/H 1600
will generate 1,600 psi for maximum output for your Dexter disc brakes. The
sealed, weather tight housing contains the electronics necessary to control the
high pressure piston pump and proportioning valve for smooth, efficient braking.
From Tow
Vehicle Controller
(Typically Blue)
+12 Volt 40 Amp
Circuit From
Tow Vehicle
Ground From
Tow Vehicle
Electrical Schematic
Traller
Plug
Charger
Lanyard
Connect
To The
Trailer ~–~ i~i~f
-28-
Blue
Note: Either an onboard or breakaway
battery may be used.
Scan to view
E/H Actuator Installation video
Troubleshooting Guide
Brakes are slow to respond
1. Re-bleed the trailer brakes and actuator.
2. If the trailer is equipped with drum brakes, readjust the drum brakes to
the brake manufacture’s recommended running clearance.
3. Slow response can be caused by trailer wiring that is too small.
4. For trailers where the E/H brake actuator is located less than 10 feet
from the tow vehicle, 12 gage wire is recommended for the black and
white wires between the tow vehicle and the E/H brake actuator. All other
wires should be a minimum of 16 gauge.
5. For trailers where the E/H brake actuator is located more than 10 feet
from the tow vehicle, 10 gage wire is recommended for the black and
white wires between the tow vehicle and the E/H brake actuator. All other
wires should be a minimum of 16 gauge.
6. Slow response can be caused by improper adjustment of the brake
controller. On inertia-based electronic brake controls, adjust the
pendulum (inertia sensor) to a more aggressive setting and/or increase
the gain setting.
Unit will not run when the ignition is on and the brake pedal is depressed
1. Verify that the trailer and tow vehicle are wired as detailed on the
electrical schematic.
2. With the ignition switch on and the brakes not applied, you should
have 12-13 volts between the black and white wires on the E/H brake
actuator.
3. Clean and replace the ground between the trailer and the E/H brake
actuator.
4. Test operation of the unit using the breakaway test procedure.
-29-

Breakaway test procedure – do not leave the breakaway switch pulled for
more than two minutes during any of the steps outlined below
1. Pull the breakaway switch on the trailer.
2. If the unit runs and builds pressure, that indicates the actuator is
functioning properly. The problem most likely is a defective electronic
brake controller in the tow vehicle or defective wiring between the tow
vehicle and the E/H brake actuator.
3. If the unit runs but will not build pressure, the problem most likely is
a defective solenoid valve in the E/H brake actuator and the actuator
should be replaced.
4. If the unit still does not run after the breakaway battery is fully charged,
verify that the voltage between the white wire and yellow wire is at least
12 volts.
5. If the voltage is less than 12 volts, either the breakaway switch or the
breakaway wiring is defective.
6. If the voltage is greater than 12 volts, the E/H brake actuator should be
replaced.
Trailer brakes too aggressive
1. Reduce the gain setting on the in-cab electronic brake controller.
-30-
General Maintenance – Hydraulic Brakes
Drum Brake Adjustment – Manual
Most Dexter 12 1/ 4″ hydraulic brakes have a self adjusting feature.
If manual adjusting is required, use the following procedure:
Brakes should be adjusted (1) after the first 200 miles of operation when the
brake shoes and drums have “seated;’ (2) at 3,000 mile intervals, (3) or as
use and performance requires. The brakes should be adjusted in the following
manner:
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturer’s recommendations for lifting and supporting the
unit. Make sure the wheel and drum rotates freely.
&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Remove the adjusting hole cover from the adjusting slot on the bottom of
the brake backing plate.
3. With a screwdriver or standard adjusting tool, rotate the star wheel of the
adjuster assembly to expand the brake shoes. Adjust the brake shoes
out until the pressure of the linings against the drum makes the wheel
very difficult to turn.
Note: For drop spindle axles, a modified adjusting tool may be
necessary.
4. Then rotate the star wheel in the opposite direction until the wheel turns
freely with a slight lining drag.
5. Replace the adjusting hole cover and lower the wheel to the ground.
6. Repeat the above procedure on all brakes. For best results, the brakes
should all be set at the same clearance.
Most of the brake components are very similar to those used in electric brakes,
and maintenance is comparable for the hub and drum, shoes and linings, and
bearings. Specific maintenance activities are as follows:
-31-

Wheel Cylinders
Inspect for leaks and smooth operation. Clean with brake cleaner and flush with
fresh brake fluid. Hone or replace as necessary.
Brake Lines
Check for cracks, kinks, or blockage. Flush with fresh brake fluid. Bleed system
to remove all air. Replace as necessary.
Shoes and Linings
A simple visual inspection of your brake linings will tell if they are usable.
Replacement is necessary if the lining is worn (to within 1/16” or less),
contaminated with grease or oil, or abnormally scored or gouged. Hairline heat
cracks are normal in bonded linings and should not be cause for concern. When
replacement is necessary, it is important to replace both shoes on each brake
and both brakes of the same axle. This will help retain the “balance” of your
brakes.
&CAUTION
POTENTIAL ASBESTOS DUST HAZARD!
Some older brake linings may contain asbestos dust, which has been
linked to serious or fatal illnesses. Certain precautions need to be
taken when servicing brakes:
1. Avoid creating or breathing dust.
2. Avoid machining, filing or grinding the brake linings.
3. Do not use compressed air or dry brushing for cleaning (dust can
be removed with a damp brush).
After replacement of brake shoes and linings, the brakes must be re-burnished
to seat in the new components. This should be done by applying the brakes 20
to 30 times from an initial speed of 40 m.p.h., slowing the vehicle to 20 m.p.h.
Allow ample time for brakes to cool between applications. This procedure allows
the brake shoes to seat in to the drum surface.
-32-
Hardware
Check all hardware. Check shoe return spring, hold down springs, and adjuster
springs for stretch or wear. Replace as required. Service kits are available.
Instructions for Brake Caliper Kit
3.5K Hydraulic Disc Brakes
Notice to Buyer
It is recommended that all brakes be replaced at the same time to ensure
balanced braking performance.
Remove the old brake caliper
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturers recommendations for lifting and supporting the
unit.
&CAUTION
Do not 11ft or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it Is properly supported on
jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Remove the wheel from the hub, leaving the brake exposed.
3. Disable the brake actuation system. Check that the hydraulic system has
zero pressure and that the hub and rotor rotate freely.
4. Remove the hose from the caliper, then remove the two caliper mounting
bolts. Do not allow the caliper to hang from the hose.
-33-

Installing the new brake caliper
1. First, inspect the brake assembly for grooves, flaking, cracks, heat
checking, thickness variation, insufficient rotor thickness, and look to
see that the mounting hardware is straight. Replace any component as
needed (or desired) per manufacturer recommendations.
2. Install the new caliper assembly. Make sure that the bleed screw points
.YQ.
3. Remount the caliper assembly onto the caliper attaching bracket.
Ensure that there is thread locking compound on the threads of the new
mounting bolts. Torque mounting bolts to 40-50 Ft. Lbs.
Note: Use two lug nuts to secure rotor against the hub face when
reassembling the caliper. After the caliper is assembled remove the lug
nuts.
4. Reconnect the hose to the elbow adapter on the back of the caliper and
torque to 10-12 Ft. Lbs.
5. Reconnect the brake actuation system. Refer to your actuation systems
Operation Maintenance Service Manual for proper operation.
6. Bleed and flush brake system per your actuation systems Operation
Maintenance Service Manual.
7. Remount the wheel. Refer to your Operation Maintenance Service
Manual for proper wheel nut torque procedures.
Instructions for Brake Rotor Kit
3.5K Hydraulic Disc Brakes
Notice to Buyer
It is recommended that all brakes be replaced at the same time to ensure
balanced braking performance.
Remove the old brake rotor
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturers recommendations for lifting and supporting the
unit.
-34-
&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
Jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Remove the wheel from the hub, leaving the brake exposed.
3. Disable the brake actuation system. Check that the hydraulic system has
zero pressure and that the hub and rotor rotates freely.
4. Remove the two caliper mounting bolts. Do not allow the caliper
assembly to hang from the hose. Do not disconnect the hose or allow air
into the hydraulic system.
5. With the caliper assembly out of the way remove the brake rotor. Save
the brake mounting hardware for reinstalling the brake calipers.
Installing the new brake rotor
1. First inspect the brake assembly for grooves, flaking, cracks, heat
checking, thickness variation, insufficient rotor thickness, and look to
see that the mounting hardware is straight. Replace any component as
needed (or desired) per manufacturer recommendations.
2. Install the new brake rotor by fitting it onto the hub flush with the hub
face.
3. Remount the caliper assembly onto the caliper attaching bracket. Place
thread locking compound on threads of mounting bolts. Torque mounting
bolts to 40-50 Ft. Lbs.
Note: Use two lug nuts to secure rotor against the hub face when
reassembling the calipers. After the calipers are assembled remove the
lug nuts.
4. Reconnect the brake actuation system. Refer to your Operation
Maintenance Service Manual for proper operation.
5. Remount the wheel. Refer to your Operation Maintenance Service
Manual for proper wheel nut torque procedures.
-35-

Instructions for Brake Rotor Kit
6K or BK Hydraulic Disc Brakes
Notice to Buyer
It is recommended that all brakes be replaced at the same time to ensure
balanced braking performance.
Remove the old brake rotor
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturers recommendations for lifting and supporting the
unit.
&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Remove the wheel from the hub, leaving the brake exposed.
3. Disable the brake actuation system. Check that the hydraulic system has
zero pressure and that the hub and rotor rotates freely.
4. For brakes produced after April 2008, locate the crossover brake line
threaded into the bottom side of both calipers. The crossover brake line
is attached to the inboard side of the anchor yoke using a metal tube
clamp. Remove the
1/ 4-20 bolt that connects the tube clamp to the yoke.
5. Remove the four caliper mounting bolts. Do not allow the caliper
assembly to hang from the hose. Do not disconnect the hose or allow air
into the hydraulic system.
6. With the caliper assembly out of the way remove the brake rotor. Save
the brake mounting hardware for reinstalling the brake calipers.
-36-
Installing the new brake rotor
1. First inspect the brake assembly for grooves, flaking, cracks, heat
checking, thickness variation, insufficient rotor thickness, and look to
see that the mounting hardware is straight. Replace any component as
needed (or desired) per manufacturer recommendations.
2. Install the new brake rotor by fitting it onto the hub flush with the hub
face.
Note: Use two lug nuts to secure rotor against the hub face when
reassembling the calipers. After the calipers are assembled remove the
lug nuts.
3. Remount the caliper assembly onto the caliper attaching bracket. It
may be necessary to push the piston into the calipers to obtain enough
clearance. Torque mounting bolts to 25-35 Ft. Lbs.
4. For brakes produced after April 2008, locate the tube clamp attached
to the crossover brake line and attach to the caliper mounting bracket.
Using the 1/4-20 bolt, torque to 85-100 In. Lbs.
5. Spin the rotor to ensure that there is enough clearance between the rotor
and the crossover brake line.
6. Reconnect the brake actuation system. Refer to your Operation
Maintenance Service Manual for proper operation.
7. Remount the wheel. Refer to your Operation Maintenance Service
Manual for proper wheel nut torque procedures.
8. Spin the wheel to ensure that there is enough clearance between the
wheel and crossover brake line or caliper.
Instructions for Brake Hub/Rotor Kit
7K Hydraulic Disc Brakes
Notice to Buyer
It is recommended that all brakes be replaced at the same time to ensure
balanced braking performance.
-37-

Remove the old brake rotor
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturers recommendations for lifting and supporting the
unit.
&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless It Is properly supported on
Jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious Injury or death.
2. Remove the wheel from the hub, leaving the brake exposed.
3. Disable the brake actuation system. Check that the hydraulic system has
zero pressure and that the hub/rotor rotates freely.
4. For brakes produced after April 2008, locate the crossover brake line
threaded into the bottom side of both calipers. The crossover brake line
is attached to the inboard side of the anchor yoke using a metal tube
clamp. Remove the
1/4-20 bolt that connects the tube clamp to the yoke.
5. Remove the four caliper mounting bolts. Do not allow the caliper
assembly to hang from the hose. Do not disconnect the hose or allow air
into the hydraulic system.
6. With the caliper assembly out of the way, remove the brake rotor by
removing the grease or oil cap, spindle nut and outer bearing, then pull
hub/rotor off the spindle.
Installing the new brake hub/rotor
1. First inspect the brake assembly for grooves, flaking, cracks, heat
checking, thickness variation, insufficient rotor thickness, and look to
see that the mounting hardware is straight. Replace any component as
needed (or desired) per manufacturer recommendations.
2. Install the new brake hub/rotor assembly and outer bearing onto axle
spindle.
3. Install washer and spindle nut onto spindle to secure hub. Install nut
per the bearing adjustment procedure in your Operation Maintenance
Service Manual.
-38-
4. Ensure spindle nut retainer is in place. Install new grease or oil cap with
rubber plug, and torque as shown on cap.
5. Remount the caliper assembly onto the caliper attaching bracket. It
may be necessary to push the piston into the calipers to obtain enough
clearance. Torque mounting bolts to 25-35 Ft. Lbs.
6. For brakes produced after April 2008, locate the tube clamp attached
to the crossover brake line and attach to the caliper mounting bracket.
Using the1/ 4-20 bolt, torque to 85-100 In. Lbs.
7. Spin the hub/rotor to ensure that there is enough clearance between the
rotor and the crossover brake line.
8. Reconnect the brake actuation system. Refer to your Operation
Maintenance Service Manual for proper operation.
9. Remount the wheel. Refer to your Operation Maintenance Service
Manual for proper wheel nut torque procedures.
10. Spin the wheel to ensure that there is enough clearance between the
wheel and crossover brake line or caliper.
Instructions for Brake Pad Kit
6K, 7K or BK Hydraulic Disc Brakes
Notice to Buyer
It is recommended that all brakes be replaced at the same time to ensure
balanced braking performance.
Remove the old brake pads
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturers recommendations for lifting and supporting the
unit.
-39-

&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
Jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Remove the wheel from the hub, leaving the brake exposed.
3. Disconnect the brake actuation system. Check that the hydraulic system
has zero pressure and that the hub and rotor rotates freely.
4. Remove the brake pad retaining pin.
5. Remove the old pads from the caliper assembly. Save the brake pad
retaining hardware for reinstalling the new pads onto the caliper.
&CAUTION
POTENTIAL ASBESTOS DUST HAZARD!
Some older brake linings may contain asbestos dust, which has been
linked to serious or fatal illnesses. Certain precautions need to be
taken when servicing brakes:
1. Avoid creating or breathing dust.
2. Avoid machining, filing or grinding the brake linings.
3. Do not use compressed air or dry brushing for cleaning (dust can
be removed with a damp brush).
Installing the new brake pads
1. First inspect the brake assembly for grooves, flaking, cracks, heat
checking, thickness variation, insufficient rotor thickness, and look to
see that the mounting hardware is straight. Replace any component as
needed (or desired) per manufacturer recommendations.
2. Press the caliper pistons into the calipers until enough clearance is
available to fit the new pads between the pistons and the rotor.
-40-
Note: Use two lug nuts to secure rotor against the hub face when
reassembling the new pads. After the pads are assembled remove the
lug nuts.
3. Install the new brake pads by sliding them in one at a time between the
caliper pistons and the rotor. The pads are the same for the inner and
outer side of the rotor. Make sure the brake lining side of the pad faces
the rotor. and the steel backing faces the caliper pistons.
4. Align the brake pad mounting holes with the holes in the caliper. Insert
one of two brake pad retaining bolts into each caliper half as shown
below in Figure 1. Place the anti-rattle spring against the brake pads
and press the center toward the rotor while you slide the outboard pad
retaining bolt toward the inner lining. Continue sliding the pad retainer
bolts until it engages both pads and pushes the second bolt out of the
inboard caliper half. Install and torque lock nut until threads stop.
Figure 1
5. Reconnect the brake actuation system. Refer to your Operation
Maintenance Service Manual for proper operation.
6. Remount the wheel. Refer to your Operation Maintenance Service
Manual for proper wheel nut torque procedures.
-41-

Instructions for Brake Caliper Kit
6K, 7K or BK Hydraulic Disc Brakes
Notice to Buyer
It is recommended that all brakes be replaced at the same time to ensure
balanced braking performance.
Remove the old brake calipers
1. Jack up trailer and secure on adequate capacity jack stands. Follow
trailer manufacturers recommendations for lifting and supporting the
unit.
&CAUTION
Do not 11ft or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless It Is properly supported on
Jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious Injury or death.
2. Remove the wheel from the hub, leaving the brake exposed.
3. Disable the brake actuation system. Check that the hydraulic system has
zero pressure and that the hub and rotor rotates freely.
4. For brakes produced after April 2008, the crossover brake line also
attaches to the inboard side of the caliper mounting bracket using the
metal tube clamp. Slide the clamp over the crossover brake line and
bend it to the closed position. Apply anti-seize or similar thread lubricant
to the 1/4-20, 1/2″ bolt. Attach the tube clamp to the threaded hole in
the caliper mounting bracket using the 1/ 4-20, 1/2″ length bolt. Torque
to 85-100 In. Lbs.
5. Remove the hose from the caliper, then remove the four caliper mounting
bolts. Do not allow the caliper to hang from the hose.
Installing the new brake caliper
1. First inspect the brake assembly for grooves, flaking, cracks, heat
checking, thickness variation, insufficient rotor thickness, and look to
see that the mounting hardware is straight. Replace any component as
needed (or desired) per manufacturer recommendations.
-42-
2. Assemble the new caliper assembly.
Note: Use two lug nuts to secure rotor against the hub face when
reassembling the calipers. After the brake is assembled, remove the lug
nuts.
3. One caliper will be used on the inboard side, with the hydraulic line
fitting adapter installed on the top side of the piston boss. The other
caliper will be used on the outboard side with the bleed screw installed
at the top of the piston boss. Install both of these calipers onto the
attaching bracket. Make sure that the bleed screw points up and is
located on the outboard caliper. Torque bolts to 25-35 Ft. Lbs.
4. Connect the new crossover brake line on the bottom sides of the piston
boss on both calipers.
Note: Make sure the crossover line fits snug around the calipers and
rotor without touching the rotor. Spin the rotor to ensure there is proper
clearance. Torque the crossover line to 12-15 Ft. Lbs. Torque the bleed
screw and the hydraulic line fitting adapter to 60-76 Inch Lbs.
5. For brakes produced after April 2008, locate the crossover brake line
threaded into the bottom side of both calipers. The crossover brake line
is attached to the inboard side of the anchor yoke using a metal tube
clamp. Remove the
1/4-20 bolt that connects the tube clamp to the yoke.
6. Reassemble the brake pads into the disc brake. Make sure to locate the
brake lining side of the pads toward the rotor surface, and the steel side
of the pads toward the calipers. Align the brake pad mounting holes with
the holes in the caliper. Insert one of two brake pad retaining bolts into
each caliper half as shown previously in Figure 1. Place the anti-rattle
spring against the brake pads and press the center toward the rotor
while you slide the outboard pad retaining bolt toward the inner lining.
Continue sliding the pad retainer bolt until it engages both pads and
pushes the second bolt out of the inboard caliper half. Install and torque
locknut until threads stop.
-43-

7. Reconnect the brake actuation system. Refer to your Operation
Maintenance Service Manual for proper operation.
8. Bleed and flush brake system per your actuation systems Operation
Maintenance Service Manual.
9. Remount the wheel. Refer to your Operation Maintenance Service
Manual for proper wheel nut torque procedures.
10. Spin wheel to ensure proper clearance between the wheel and crossover
brake line or caliper.
-44-
Introduction to Troubleshooting
Proper brake function is critical to the safe operation of any vehicle. A properly
installed vacuum/hydraulic, electric/hydraulic, or air/hydraulic system should
not require any special attention with the exception of routine maintenance as
defined by the manufacturer. If problems occur, the entire tow vehicle/trailer
braking system should be analyzed by a qualified mechanic. Typical problems in
a hydraulic braking system are:
Air or vacuum leaks
Hydraulic system leaks
Air in brake lines
Water or other impurity in brake fluid
Rusted or corroded master or wheel cylinders
Actuation system malfunction
Please consult the following troubleshooting charts to determine the causes and
solutions for common problems found in trailer braking systems.
CAUTION
The maximum operating pressure for Dexter brakes:
7″ diameter drum brakes
maximum operating pressure is 750 psi
10″ diameter and larger drum brakes
maximum operating pressure is 1,000 psi
Hydraulic disc brakes (all sizes)
maximum operating pressure is 1,600 psi
-45-

Troubleshooting
SYMPTOM CAUSES REMEDIES
Broken or Kinked Repair or Replace Brake Line
No Brakes Severe Underadjustment Adjust Brakes
Malfunctioning
Actuation System Troubleshoot System
Brake Adjustment Manual-Adjust Brakes Not Correct Automatic-Make Several Reverse Stops
Excessively Worn Replace Shoe
Brake Linings and Lining
Incorrect Lining Install Correct
Shoe and Lining
Grease or Fluid Repair Grease Seal or
Soaked Lining Wheel Cylinder. Install
New Shoe and Lining.
Frozen Master Cylinder Recondition or Replace
or Wheel Cylinder Pistons All C linders, Brake Fluid
Weak Brakes
Glazed Lining Reburnlsh or Replace
Excessive Drum Wear Replace
(,) ·– ::::s Trapped Air In Lines Bleed System e
~ Overloaded Traller Correct
::c Malfunctioning Troubleshoot
Actuating System System
en
E Brake Adjustment Manual-Adjust Brakes
Automatic-Make Several
.C..l,) Not Correct Reverse Stops Harsh Brakes
~ Grease or Fluid Replace Shoes
U) on Linings and Linings
’00 Grease or Oil Clean or Replace C on Linings ·.:.-:: Surging Brakes e Out Corfa Rcokuend dD Drurumms s or Machine or Replace m
-46-
Troubleshooting m ;
SYMPTOM CAUSES REMEDIES -::ii·=- ::::s
C10.
Underadjustment Adjust
~
Lack of Lubrication Lubricate .C.l.).
Noisy Brakes CD
Broken Brake Replace Components 3 Components Cl)
Incorrect Brake Correct Components ::c
‘<
Loose, Bent or Broken Replace Components CL
Brake Components ;
Locking Brakes C
Underadjustment Adjust –· C,
Out-of-Round Drums Machine or Replace
Incorrect Tire Inflate Evenly on Both
Pressure Sides to R . Pressures
Pulls to One Side Unmatched Tires
on Same Axle
Match Tires on Axle
Restricted Brake Repair or Replace
Lines or Hoses
Malfunctlonln~ Cylinder Check for Stuck
Assem I or Sluggish Pistons
Defective or Damaged Install New Shoe and
Shoe and Llnln Llnln -Com lete Axle
One Side Adjust Out-of-Adjustment
Improper Fluid Replace Rubber Parts
FIii with DOT4 Fluld
Blocked Master Open with Comgressed
Cylinder Air or Replace yllnder
Dragging
Parking Brake Free Cable
Cable Frozen and Lubricate
Improper Lining Install New Shoes
Thickness or Location and Linings

Hubs/Drums/Bearings
Dexter offers several types of bearing arrangements and lubrication methods.
Dexter’s standard wheel bearing configuration consists of opposed
tapered roller bearing cones and cups, fitted inside of a precision
machined cast hub. This method of using tapered roller bearings requires
that a minimal amount of axial end play be provided at assembly. This
end play is essential to the longevity of the bearings service life. This
design is typically lubricated with grease, packed into the bearings. Oil
lubrication is another method which is available in some of the larger
axle capacities.
E-Z Lube” is another option chosen by some trailer manufacturers. If
your axle is equipped with the Dexter E-Z Lube” feature, the bearings can
be periodically lubricated without removing the hubs from the axle. This
feature consists of axle spindles that have been specially drilled and
assembled with grease fittings in their ends. When grease is pumped into
the fitting, it is channeled to the inner bearing and then flows back to the
outer bearing and eventually back out the grease cap hole.
Nev-R-Lube” option is the latest innovation from Dexter. Nev-R-Lube”
bearings are comprised of opposed tapered roller bearing cones sealed
inside of a precision ground, one piece double cup arrangement. These
bearings are designed with a small amount of axial end play. This end
play is essential to the longevity of the bearings service life. They are
lubricated, assembled and sealed at the factory. No further lubrication is
ever needed.
Before attempting any disassembly of your Dexter axle, make sure you read and
follow the instructions for the appropriate axle type.
Scan to view
Bearing Maintenance video
-48-
Hub Removal – Standard Bearings
Whenever the hub equipment on your axle must be removed for inspection or
maintenance the following procedure should be utilized.
1. Elevate and support the trailer unit per manufacturers’ instructions.
&CAUTION
You must follow the maintenance procedures to prevent damage
to important structural components. Damage to certain structural
components such as wheel bearings can cause the wheel end to come
off of the axle. Loss of a wheel end while the trailer is moving can
cause you to lose control and lead to an accident, which can result in
serious injury or death.
2. Remove the wheel.
3. Remove the grease cap by carefully prying progressively around the
flange of the cap. If the hub is an oil lube type, then the cap can be
removed by unscrewing it counterclockwise while holding the hub
stationary.
4. Remove the cotter pin from the spindle nut.
For E-Z Lube” axles produced after February of 2002, a new type of
retainer is used. Gently pry off retainer from the nut and set aside.
5. Unscrew the spindle nut (counterclockwise) and remove the spindle
washer.
6. Remove the hub from the spindle, being careful not to allow the outer
bearing cone to fall out. The inner bearing cone will be retained by the
seal.
Brake Drum Inspection
There are two areas of the brake drum that are subject to wear and require
periodic inspection. These two areas are the drum surface where the brake
shoes make contact during stopping and the armature surface where the
magnet contacts (only in electric brakes).
The drum surface should be inspected for excessive wear or heavy scoring. If
worn more than .020″ oversized, or the drum has worn out of round by more
-49-

than .015″, then the drum surface should be re-machined. If scoring or other
wear is greater than .090″ on the diameter, the drum must be replaced. When
turning the drum surface, the maximum rebore diameter is as follows:
7″ Brake Drum-7.090″ diameter
10″ Brake Drum-10.090″ diameter
12″ Brake Drum-12.090″ diameter
12 1/4″ Brake Drum-12.340″ diameter
6K, 7K and 8K Rotor-1.03″ minimum thickness
3.5K Rotor-.85″ minimum thickness
The machined inner surface of the brake drum that contacts the brake magnet
is called the armature surface. If the armature surface is scored or worn
unevenly, it should be refaced to a 120 micro inch finish by removing not more
than .030″ of material. To ensure proper contact between the armature face
and the magnet face, the magnets should be replaced whenever the armature
surface is refaced and the armature surface should be refaced whenever the
magnets are replaced.
Note: It is important to protect the wheel bearing bores from metallic chips
and contamination which result from drum turning or armature refacing
operations. Make certain that the wheel bearing cavities are clean and free
of contamination before reinstalling bearing and seals. The presence of these
contaminants will cause premature wheel bearing failure.
Bearing Inspection
Wash all grease and oil from the bearing cone using a suitable solvent. Dry the
bearing with a clean, lint-free cloth and inspect each roller completely.
CAUTION
Never spin the bearing with compressed air.
THIS CAN DAMAGETHE BEARING.
-50-
If any pitting, spalling, or corrosion is present, then the bearing must be
replaced. The bearing cup inside the hub must be inspected.
IMPORTANT: Bearings must always be replaced in sets of a cone and a cup.
&CAUTION
Be sure to wear safety glasses when removing or Installing force
fitted parts. Failure to comply may result In serious eye Injury.
When replacing the bearing cup proceed as follows:
1. Place the hub on a flat work surface with the cup to be replaced on the
bottom side.
2. Using a brass drift punch, carefully tap around the small diameter end of
the cup to drive out.
3. After cleaning the hub bore
area, replace the cup by
tapping in with the brass drift
punch. Be sure the cup is
seated all the way up against
the retaining shoulder in the
hub.
Replace only with bearings as specified
in the Bearing Replacement Chart.
-51-

Bearing Lubrication – Grease
CAUTION
Do not mix Lithium, calcium, sodium or barium complex greases due
to possible compatibility problems. When changing from one type of
grease to another, it is necessary to ensure all the old grease has
been removed.
Along with bearing adjustment, proper lubrication is essential to the proper
function and reliability of your trailer axle. Bearings should be lubricated every
12 months or 12,000 miles. The method to repack bearing cones is as follows:
1. Place a quantity of grease into the palm of your hand.
2. Press a section of the widest end of the bearing into the outer edge of
the grease pile closest to the thumb forcing grease into the interior of the
bearing.
3. Repeat this while rotating the bearing
from roller to roller.
4. Continue this process until you have
the entire bearing completely filled
with grease.
5. Before reinstalling, apply a light coat
of grease on the bearing cup.
Bearing Lubrication – Oil
If your axles are equipped with oil lubricated
hubs, periodically check and refill the hub as necessary with a high quality
hypoid gear oil to the level indicated on the clear plastic oil cap. The oil can be
filled from either the oil fill hole, if present, in the hub or through the rubber plug
hole in the cap itself.
-52-
Recommended Wheel Bearing
Lubrication Specifications
Grease
Thickener Type Lithium Complex
Dropping Point 215°C (419°F) Minimum
Consistency NLGINo.2
Additives EP, Corrosion & Oxidation Inhibitors
Viscosity Index 80 Minimum
Approved Grease Sources
Chem Arrow Arrow 2282
Chevron Texaco Chevron Ulti-Plex Grease EP #2
Texaco Starplex Moly MPGM #2
Citgo Lithoplex MP #2
Lithoplex CM #2
Mystik JT-6 Hi-Temp Grease #2
ConocoPhillips/ Multiplex RED #2
76 Lubricants/Kendall L427 Super Blu Grease
Dexter Company Lithoplex Red MP #2
Exxon/Mobil Company Ronex, MP
Mobilith AW 2
Mobil I Synthetic Grease
Fuchs Renolit Uniwrl 2
Great Plains Lubricants Lithium Complex EP #2
Oil Center Research Liquid-0-Ring No, 167L
of Oklahoma
Pennzoil-Quaker State Synthetic Red Grease
Company
Royal Mfg. Company Royal 98 Lithium Complex EP #2
Shell Gadus S3 V220C
Gadus S5 V220
Rotella Heavy Duty Lithium
Complex#2
Valvoline Valvoline Multi-Purpose GM
Valvoline DuraBlend
-53-

Oil I SAE 90, SAE 80W-90, SAE 75W-90
Approved Oil Sources
Ashland Oil Valvoline DuraBlend
CITGO Petroleum Co. CITGO Premium Gear Oil MP
MystikJT-7
Mystik Power Lube
Conoco Universal Gear Lubricant 80W-90
Exxon Company USA Gear Oil GX 80W-90
Industrial Oils Unlimited Super MP Gear Oil 80W-90
Kendall Refining Co. Kendall NS-MP Hypoid Gear Lube
Lubriplate Division/ Lubriplate APG 90
Fiske Brothers Refining
MFA Oil Company Multi-Purpose Gear Oil 80W-90
Mobil Oil Corporation Mobilube SHC
Mobil 1 Synthetic Gear Lube
Phillips 66 Petroleum Superior Multi-Purpose Gear Oil
Philguard Gear Oil
Philsyn Gear Oil
Pennzoil Products Co. Gear Plus 80W-90 GL-5
Gear Plus Super 75W-90
Gear Plus Super EW 80W-90
Multi-Purpose 4092 Gear Lube
Oil Center Research Liquid-0-Ring 750 GX
Sun Refining and Marketing Sunoco Ultra
Company Sunoco Dura Gear
Shell Oil Company SpiraxA
Spirax G
Spirax HD
Spirax S
Texaco Oil Company Multigear EP
Multigear SS
Troco Division/ Multigear Select Gear Oil
Royal Manufacturing
Union Oil Company Unocal MP Gear Lube
76 Triton Syn Lube EP
-54-
Note: The convenient lubrication provisions of the E-Z Lube” and the oil
lubrication must not replace periodic inspection of the bearings.
Seal Inspection and Replacement
Whenever the hub is removed, inspect the seal to assure that it is not nicked
or torn and is still capable of properly
sealing the bearing cavity. If there is
any question of condition, replace the
seal. Use only the seals specified in the
Seal Replacement Chart.
To replace the seal:
1. Pry the seal out of the hub
with a seal removal tool or a
screwdriver. Never drive the seal
out with the inner bearing as
you may damage the bearing.
Bad Seal: Nicks and Tears
(REPLACE SEAL)
2. Apply a sealant similar to PERMATEX” High-Temp Red R1V Silicone
Gasket to the outside of the seal. Use only enough to provide a thin coat
to prevent any excess from contaminating the rubber lip(s) of the seal. It
is okay to apply a slight amount of lube to the inner rubber lip(s) to aid
with installing onto the spindle.
Note: No sealant should be used if the outside of the seal is rubber
coated. For these type of seals it is recommended to apply a thin coat of
oil to the outside rubber.
3. Clean the seal journal of the spindle to inspect for nicks or roughness.
Use a file to remove any burrs from the leading edge or shoulder area.
Clean the journal area with very fine emery cloth. Any presence of deep
gouges or scratches in this area may cause seal failure allowing lubricant
to leak out of the hub.
4, Clean the seal bore in the hub and inspect for any nicks, gouges, or
scratches that may prevent the seal from retaining the bearing lubricant
inside the hub.
-55-

5. Orient the seal properly. Many oil bath seals will be marked AIR SIDE on
the side of the seal to facing out of the hub after installation.
6. Install new seal into place using a seal driver or seal installation tool
of proper size. It is important that any seal installation tool contact the
outer ring of the seal casing. If no seal driver is available, use a clean
block of wood. It is critical that the seal be driven in evenly and straight
NEVER hammer directly on the seal.
7. The seals will be pressed flush to the back surface of the hub in the
600-8,000 lbs. capacity product line. It is NEVER necessary to bottom
out the seal for proper installation. Driving the seal in too deep may
damage the seal and may come in contact with the inner bearing
preventing it from rotating freely.
8. Proper installation will maintain the seal flatness in the hub within .010″.
A seal that is cocked too much inside the hub will be more likely to leak.
Bearing Adjustment and Hub Replacement
If the hub has been removed or bearing adjustment is required, the following
adjustment procedure must be followed.
For standard grease or oil axles using cotter pin:
1. After placing the hub, bearings, washers, and spindle nut back on the
axle spindle in reverse order as detailed in the previous section on hub
removal, rotate the hub assembly slowly while tightening the spindle nut
to approximately 50 Ft. Lbs. (12″ wrench or pliers with full hand force.)
2. Then loosen the spindle nut to remove the torque. Do not rotate the hub.
3. Finger tighten the spindle nut until just snug.
4. Back the spindle nut out slightly until the first castellation lines up with
the cotter key hole and insert the cotter pin.
5. Bend over the cotter pin legs to secure the nut.
6. Nut should be free to move with only restraint being the cotter pin.
-56-
For E-Z Lube” axles using the new nut retainer:
1. After placing the hub, bearings, washers, and spindle nut back on the
axle spindle in reverse order as detailed in the previous section on hub
removal, rotate the hub assembly slowly while tightening the spindle nut
to approximately 50 Ft. Lbs. (12″ wrench or pliers with full hand force.)
2. Then loosen the spindle nut to remove the torque. Do not rotate the hub.
3. Finger tighten the nut until just snug, align the retainer to the machined
flat on the spindle and press the retainer onto the nut. The retainer
should snap into place. Once in place, the retainer/nut assembly should
be free to move slightly.
4. If the nut is too tight, remove the retainer and back the nut off
approximately one twelfth of a turn and reinstall the retainer. The nut
should now be free to move slightly.
5. Reinstall grease cap.
Typical E-Z Lube”‘ After Spring 2002
E-Z Lube”‘ Lubrication
The procedure is as follows:
“D”Washer Nut Retainer
1. Remove the rubber plug from the end of the grease cap.
2. Place a standard manual grease gun onto the grease fitting located in
the end of the spindle. Make sure the grease gun nozzle is fully engaged
on the fitting.
3. While rotating the hub, pump grease slowly into the fitting. The old
displaced grease will begin to flow back out the cap around the grease
gun nozzle.
-57-

4. When the new clean grease is observed, remove the grease gun, wipe off
any excess, and replace the rubber plug in the cap.
5. Rotate hub or drum while adding grease.
Note: The E-Z Lube• feature is designed to allow immersion in water.
Axles not equipped with E-Z Lube” are not designed for immersion and
bearings should be repacked after each immersion. If hubs are removed
from an axle with the E-Z Lube” feature, it is imperative that the seals be
replaced BEFORE bearing lubrication. Otherwise, the chance of grease
getting on brake linings is greatly increased.
Note: Dexter strongly recommends not using pneumatic powered grease
guns as these can inject grease too fast and force grease past the seal,
or in rare cases dislodge the seal.
Grease Fitting /
Metal End Cap
-58-
Nev-R-Lube® Drums/Bearings
Dexter’s Nev-R-Lube” bearings are comprised of opposed tapered roller bearing
cones sealed inside of a precision ground, one piece double cup arrangement.
These bearings are designed with a small amount of axial end play. This end
play is essential to the longevity of the bearings service life.
Note: Nev-R-Lube” is not designed for immersion in water, such as boat trailer
use.
CAUTION
Dexter has advised trailer manufacturers of certain wheel limitations
when used with the Nev-R-Lube” bearings. The offset of the wheel
must be as listed. Deviation from these limits will result in limited
bearing life and possible catastrophic failure.
35MM – use only zero offset wheels
42MM – use only zero offset wheels
50MM – use only zero offset to .19″ wheels
-59-

Drum Removal
Whenever the hub equipment on your axle must be removed for inspection or
maintenance, the following procedure should be utilized.
1. Elevate and support the trailer unit per manufacturer’s instructions.
&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Remove the wheel.
3. Remove the grease cap from the hub by carefully prying progressively
around the flange.
4. Remove snap ring on the end of the spindle. Remove “torque instruction”
washer.
5. Unscrew the spindle nut (counterclockwise) and remove the spindle
washer.
6. Carefully remove the hub from the spindle. The Nev-R-Lube” bearing
cartridge will remain in the hub.
Note: Do not remove cartridge bearing from the hub bore unless
replacement of the bearing cartridge is intended. Special tools and
techniques are required for removal of the old bearing.
Bearing Inspection
Important:
1. Elevate and support the trailer unit per manufacturer’s instructions.
-60-
&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Check for excessive wheel end clearance by pulling the tire assembly
towards you and by pushing the assembly away from you. Slight end play
is acceptable.
3. Rotate tire slowly forwards and backwards. The wheel assembly should
turn freely and smoothly.
4. Excessive wheel end play, restriction to rotation, noise, or “bumpy”
rotation should be remedied by replacing the bearing unit.
5. Bearing units should be inspected every year or 12,000 miles whichever
comes first.
Note: A slight amount of grease weeping from the seal area is normal.
Excessive leakage may indicate abnormal bearing operation.
Nev-R-Lube® Bearing End Play Inspection
The following lists the maximum axial end play for each of the sizes of
Nev-R-Lube” bearings and the amount of tilt that can be expected. Since there
are a large number of wheel and tire combinations in use on trailers, the tilt is
expressed in inches per inch. The movement as measured at the tire tread can
be found by the following method:
Example: if the tilt value is shown as .003″ per inch and the tire
measures 30″ in diameter, simply multiply .003″ X 15″ (1/2 tire
diameter) = .045″ which is the total expected movement at the tires’
outer diameter.
-61-

Resultant Tilt Value
Bearing Size End Play
35 MM .005″ axial .003″ / per inch
42 MM .006″ axial .005″ / per inch
50MM .008″ axial .004″ / per inch
It is important to note that most mounted tires will deflect fairly easily when
enough hand pressure is applied while shaking the tire. Excessive pressure
will result in the perception that the bearings’ tilt is greater than it actually is.
This same phenomenon will occur when checking any wheel end, even those
equipped with conventional bearing sets.
Bearing Replacement and Drum Installation
1. Once the drum and bearing
assembly is removed from the
axle, remove “internal” snap ring
from the bearing bore that retains
bearing.
2. Using an arbor press and
mandrel, press the bearing out of
the drum. Bearing will exit on the
wheel side of the drum.
3. When replacing a Nev-R-Lube•
bearing pack, the bore in the hub
should be cleaned and inspected
for visual damage (replace as
necessary).
4. Install the new bearing using an
arbor press fitted with a hollow
or stepped punch face to press
only on the outer housing of
the bearing. Failure to follow
procedure will damage the
bearing and/or seals during
installation. Press bearing until
it seats against the backup
shoulder machined into the
hub.
-62-
LJ Hydraulic lr-~-J/”/ Press
U —-Bearing
r:—-:1—-
L.:……….l.
5. Install “internal” snap ring into hub.
6. Clean and inspect spindle shaft. Apply a light coating of anti-seize
lubricant to the spindle shaft prior to assembling drum.
7. Install drum assembly onto spindle (Do NoT FORCE).
8. Install steel washer onto spindle end.
9. Start self-locking nut onto spindle thread by hand. Complete installation
using a 1 7 /16″ 6 or 12 point socket and torque wrench. Nut should
be torqued to 145-155 Ft. Lbs. (this torque will set the internal bearing
adjustment, no other adjustments are to be made).
10. Install “torque instruction” washer onto end of spindle.
11. Install “external” snap ring onto end of spindle to retain washer.
12. Inspect assembly for excessive end play, noise, and rotation restriction
prior to mounting final wheel end hardware.
-63-

Axle & Suspension Installation
Responsibility for proper axle alignment lies with the axle installer. The axle must
be installed so that it will be parallel to the drive axle(s) of the tractor. This will
allow good vehicle control when cornering, longer tire wear, and it will eliminate
dog tracking. Alignment can be determined by measuring from the center of the
trailer king pin to the center of each end of the axles. The difference should not
vary by more than 1/16″. In the case of multiple axles, the axles must also be
in line with each other. The difference between the centers of one axle and end
centers of the other axle must not vary more than 1/8″.
&CAUTION
Safety glasses should be worn at all times when assembling or
disassembling axles and their components.
Dexter tubular axles are made of high strength steel for better fatigue life and
superior welding qualities. The round tubular axles provide a uniform section
modulus no matter how the beam is rotated.
-64-
Suspension Systems
The suspension systems incorporated into Dexter axles are designed to provide
the trailer owner three basic functions:
1. Attach the axle to the trailer
2. Dampen the effects of road shock
3. Cushion the cargo or load
All Dexter suspension systems are available in single and multiple axle
configurations. The three types most commonly available are double eye leaf
spring, slipper spring, and Torflex•.
Double Eye Leaf Springs
Double eye springs have eyes formed in each end of the spring with anti-friction
bushings fitted for wear resistance. The springs are held to the axle tube using a
system of U-bolts and tie plates and are attached to the trailer as shown.
Underslung Shown
Rear
Hanger
Articulation of this suspension occurs when the spring becomes loaded
and consequently lengthens. The double pivot action of the shackle links
accommodates this articulation and allows the system to move freely.
In multiple axle installations, the action is the same with the additional
movement of the equalizer assembly. This serves to transfer instantaneous loads
from one axle to another in an effort to “equalize” the load between the axles.
-65-

Grease Lubricated Suspension Bushings
Dexter offers a variety of optional heavy duty attaching parts kits for double
eye leaf spring suspensions up to 8,000 lb. axle capacity. The kits contain extra
heavy shackle links, bronze bushings for the spring eyes, and suspension bolts
and equalizers equipped with grease fittings to provide a convenient means
to lubricate all the pivot points including the rubber E-Z Flex• equalizer center
bushings. For availability, contact your nearest Dexter facility or visit us online at
www.dexteraxle.com for a complete listing of genuine repair parts.
SHpperLeafSprings
Slipper springs have an eye formed in one end only, with the other end formed
into a reverse curve. The attachment of these springs is as follows:
1. The front eye is attached directly into the front hanger with a bolt and
nut.
2. The rear end of the spring is captured in the rear hanger or equalizer with
a “keeper bolt” that prevents the spring from coming out when the trailer
is jacked up for service.
Equalizer Center Hanger
Spring Eye Bolts Keeper Bolts
Overslung Shown
Rear
Hanger
The articulation of this suspension occurs when the rear end of each slipper
en spring slides against the wear surfaces provided in the rear hangers or S equalizers. This suspension is also available in single and multiple axle
•;; configurations.

-66-
Inspection and Replacement
All the components of your suspension system should be visually inspected
at least every 6,000 miles for signs of excess wear, elongation of bolt holes,
and loosening of fasteners. Whenever loose or replaced, the fasteners in your
suspension system should be torqued as detailed in the charts below. All wet
bolts and equalizers should be greased every 3,000 miles.
&CAUTION
You must follow the maintenance procedures to prevent damage
to Important structural components. Damage to certain structural
components such as wheel bearings can cause the wheel to come
off of the axle. Loss of a wheel end while the trailer is moving can
cause you to lose control and lead to an accident, which can result in
serious injury or death.
Suspension Fastener Torque Values
Torque (Ft. Lbs.)
Item Min Max
3/8″ U-Bolt 30 50
7/16″ U-Bolt 45 70
1/2″ U-Bolt 70 80
1/2″ U-Bolt;Hex Nut 45 70
1/2″ Flange Nut 70 80
9/16″ U-Bolt 65 95
5/8″ U-Bolt 100 120
Non shoulder type with 9/16″ threads
Shackle Bolt Snug fit only. Parts must rotate freely. Locking nuts
Spring Eye Bolt or cotter pins are provided to retain nut-bolt
Equalizer Bolt assembly.
Shoulder Type I 30 I 50
Shackle Bolt with 7 / 16″ threads
Worn spring eye bushings, sagging springs, or broken springs should be replaced
using the following method.
1. Support the trailer with the wheels just off the ground.
-67-

Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. After the unit is properly supported place a suitable block under the axle
tube near the end to be repaired. This block is to support the weight of
the axle only, so that suspension COMPONENTS can be removed.
3. Disassemble the U-bolts, nuts, and tie plates.
4. Remove the spring eye bolts and remove the spring and place on a
suitable work surface.
5. If the spring eye bushings are to be replaced, drive out the old bushing
using a suitable drift punch.
&CAUTION
Be sure to wear safety glasses when removing or lnstalllng force
fitted parts. Failure to comply may result In serious Injury.
6. Drive the new bushing into the spring eye using a piloted drift punch or a
close fitting bolt inserted through the bushing.
7. Reinstall repaired or replaced components in reverse order.
Note: For multiple axle units, the weight of each axle must be supported
as outlined in Step 2 before disassembly of any component of the
suspension system.
= If the equalizer or equalizer bushings must be replaced, follow the instructions above for lifting and supporting the trailer unit and then proceed as follows:

-68-
1. With both axles blocked up, remove the spring eye bolt, shackle bolt, and
equalizer bolt from the equalizer to be repaired or replaced.
2. Take the equalizer to suitable work surface and remove the worn
bushings using a suitable drift punch.
3. Drive the new bushings into place using a piloted drift punch or a close
fitting bolt through the bushing.
4. Reassemble in reverse order.
&CAUTION
Be sure to wear safety glasses when removing or installing force
fitted parts. Failure to comply may result in serious injury.
All of the pivot points on your standard suspension system have been fitted
with anti-friction bearing materials which do not require routine lubrication.
When otherwise servicing the unit, these pivot points may be lubricated if you so
desire. If your trailer has been fitted with the Heavy Duty Attaching Parts Kit, you
should lubricate periodically to ensure long component life.
Tort/ex® Suspension
The Torflex• suspension system is a torsion arm type suspension which is
completely self contained within the axle tube. It attaches directly to the
trailer frame using brackets which are an integral part of the axle assembly.
The Torflex• axle provides improved suspension characteristics relative to leaf
spring axles through the unique
arrangement of a steel torsion
bar surrounded by four natural
rubber cords encased in the
main structural member of the
axle beam.
The wheel/hub spindle is
attached to a lever, called the
torsion arm, which is fastened
to the rubber encased bar. As
load is applied, the bar rotates
causing a rolling/compressive
-69-
Mounting Bracket AxleTUbe
Torsion Arm

resistance in the rubber cords. This action provides the same functions
as conventional sprung axles with several operating advantages including
independent suspension.
Except for periodic inspection of the fasteners used to attach the Torflex•
axle to the vehicle frame, no other suspension maintenance is required on
Torflex• axles. They are, of course, subject to the maintenance and inspection
procedures regarding brakes, hubs, bearings, seals, wheels, and tires as outlined
in this manual.
CAUTION
DO NOT WELD ON THE TORFLEX0 BEAM. It has rubber cords inside and
the heat generated by welding could damage the cords.
Airflexlb Suspension
The Dexter Airflex• suspension is a unique combination ofTorflex• axle and
conventional air suspension technology. This low maintenance suspension
system carries the load on a cushion of air, usually supplied by an on-board
compressor and storage tank. A load leveling valve maintains a constant
ride height, regardless of load. As load is added to the trailer, the valve
will automatically signal the compressor to supply more air. As loads are
removed, the same valve will exhaust air to maintain the same height and ride
characteristics.
The Airflex· suspension air generation kit has a built in dump valve which allows
the trailer to be lowered several inches to facilitate loading or leveling. Once
loaded, the valve is reversed and the system is pressurized to raise the trailer
back up to normal running height.
Axle Adjustment
1. Support the trailer frame on a level surface. If the wheels are already
= mounted, make sure they are clear of the ground. If the air actuation system has been installed, make sure the air pressure in the air bags is
c bled off before lifting the trailer. ·-Cl)

-70-
Note: Lifting the trailer with air system pressurized will overextend the air
bags and can result in damage to the air bags.
&CAUTION
Do not lift or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless it is properly supported on
jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious injury or death.
2. Measure from king pin to spindle center on each side. To simplify this
process, plumb lines may be dropped from the king pin and from the
center line of each spindle end. Measurements “fi!.’ and “B” can then be
taped on the floor to eliminate any miss measurement due to sagging of
the tape for long measurements. Compare A and B measurements (see
Figure 1).
3. Suspension front pivot connection is torqued to 270 Ft. Lbs. when the
suspension is shipped. The axle should be aligned on the trailer in this
condition.
-71-

Wheels
Wheel Selection
Wheels are a very important and critical component of your running gear
system. When specifying or replacing your trailer wheels it is important that
the wheels, tires, and axle are properly matched. The following characteristics
are extremely important and should be thoroughly checked when replacement
wheels are considered.
1. Bolt Circle. Many bolt circle dimensions are available. Some vary by so
little that it might be possible to attach an improper wheel that does not
match the axle hub. Be sure to match your wheel to the axle hub.
2. Capacity. Make sure that the wheels have enough load carrying capacity
and pressure rating to match the maximum load of the tire and trailer.
3. Offset. This refers to the relationship of the center line of the tire to the
hub face of the axle. Care should be taken to match any replacement
wheel with the same offset wheel as originally equipped. Failure to
match offset can result in reducing the load carrying capacity of your
axle.
4. Rim Contour.
&CAUTION
Replacement tires must meet the same specifications as the
orlglnals. Mismatched tires and rims may come apart with explosive
force and cause personal Injury to yourself or others. Mismatched
tires and rims can also blow out and cause you to lose control and
have an accident which can result In serious Injury or death.
-72-
&CAUTION
Do not attempt to repair or modify a damaged wheel. Even minor
modifications can cause a dangerous failure of the wheel and result
in personal injury or death.
Torque Requirements
In June of 2004, Dexter ceased production of trailer wheels. If your vehicle is
equipped with Dexter steel wheels manufactured before that date, the following
wheel torque information will be applicable.
If your trailer is equipped with wheels produced by other manufacturers, you
must consult with the vehicle manufacturer to determine the appropriate torque
level for your wheels. However, you must not exceed the limits of the wheel
mounting studs on the axles.
It is extremely important to apply and maintain proper wheel mounting torque
on your trailer axle. Torque is a measure of the amount of tightening applied to
a fastener (nut or bolt) and is expressed as length force. For example, a force of
90 pounds applied at the end of a wrench one foot long will yield 90 Ft. Lbs.
of torque. Torque wrenches are the best method to assure the proper amount of
torque is being applied to a fastener.
&CAUTION
Wheel nuts or bolts must be tightened and maintained at the proper
torque levels to prevent loose wheels, broken studs, and possible
dangerous separation of wheels from your axle, which can lead to an
accident, personal injuries or death.
Be sure to use only the fasteners matched to the cone angle of your wheel
(usually 60° or 90°). The proper procedure for attaching your wheels is as
follows:
1. Start all bolts or nuts by hand to prevent cross threading.
2. Tighten bolts or nuts in the sequence shown for Wheel Torque
Requirements.
-73-

3. The tightening of the fasteners should be done in stages. Following
the recommended sequence, tighten fasteners per wheel torque
requirements diagram.
4. Wheel nuts/bolts should be torqued before first road use and after each
wheel removal. Check and re-torque after the first 10 miles, 25 miles,
and again at 50 miles. Check periodically thereafter.
Wheel Torque Requirements
Wheel Installation Torque Sequence (Ft. Lbs.)
Wheel Stud 1st 2nd Final
Size Size Stage Stage Torque
12″ – 440 BC 1/2″-20 20-25 35-40 60-75
12″ – 545 BC 1/2″-20 20-25 35-40 60-75
13″ – 440 BC 1/2″-20 20-25 35-40 60-75
13″ – 545 BC 1/2″-20 20-25 35-40 60-75
14″ – 545 BC 1/2″-20 20-25 50-60 100-120
15″ – 545 BC 1/2″-20 20-25 50-60 100-120
15″ – 655 BC 1/2″-20 20-25 50-60 100-120
16″ – 655 BC 1/2″-20 20-25 50-60 100-120
16″ – 865 BC 9/16″-18 20-25 50-60 140-170
16.5″ – 655 BC 1/2″-20 20-25 50-60 100-120
16.5″ – 865 BC 9/16″-18 20-25 50-60 140-170
16.5″ X 9.75″ 5/8″-18 50-60 120-125 175-225
865 BC
17.5″ Hub Pilot 5/8″-18 50-60 100-120 190-210
865 BC
17.5″ Hub Pilot 5/8″-18 50-60 90-200 275-325
865 BC
17.5″ Hub Pilot 5/8″-18 50-60 60-110 150-175
865 BC
-74-
Cone Nut
Degree
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
60° Cone Nut
Special Stud Piloted
With 90° Cone
Nuts
Hub Piloted With
Clamp Ring. 90°
Cone Nuts &
Greased Threads
Hub Piloted With
Range Nut
Hub Piloted With
Swivel Flange Nut
1 1 1 1 ·O· t)· :o:-a, 2 2 2
4 BOLT 5 BOLT 6 BOLT 8 BOLT
Maximum Wheel Fastener Torque
The wheel mounting studs used on Dexter axles conform to the SAE standards
for grade 8. The maximum torque level that can be safely applied to these studs
is listed in the following chart:
Stud Size Maximum Torque
1/2″-20 UNF, class 2A 120 Ft. Lbs.
9/16″-18 UNF, class 2A 170 Ft. Lbs.
5/8″-18 UNF, class 2A 325 Ft. Lbs.
&CAUTION
Exceeding the above listed torque limits can damage studs and/ or
nuts and lead to eventual fractures and dangerous wheel separation.
CAUTION
Dexter’s patented Torq-N-Go™ swiveling wheel nut generates
significantly more clamp load than standard wheel nuts. Do not
exceed the specified torque or the wheel and/or stud may be
damaged. Special caution should be observed with steel wheels.
Some steel center discs may not be able to withstand the Torq-N-Go'”
wheel nuts’ specified operating torque. It is the responsibility of the
trailer manufacturer to assure that its’ wheels are compatible with
this wheel nut.
-75-

Tires
Before mounting tires onto the wheels, make certain that the rim size and
contour is approved for the tire as shown in the Tire and Rim Association
Yearbook or the tire manufacturers catalog. Also make sure the tire will carry the
rated load. If the load is not equal on all tires due to trailer weight distribution,
use the tire rated for the heaviest wheel position.
Note: The capacity rating molded into the sidewall of the tire is not always
the proper rating for the tire if used in a trailer application. Use the following
guidelines:
1. LT and ST tires. Use the capacity rating molded into the tire.
2. Passenger Car Tires. Use the capacity rating molded into the tire sidewall
divided by 1.10 for trailer use.
Use tire mounting procedures as outlined by the Rubber Manufacturer’s
Association or the tire manufacturers.
Tire inflation pressure is the most important factor in tire life. Inflation pressure
should be as recommended by the manufacturer for the load. Pressure should
be checked cold before operation. Do not bleed air from tires when they are hot.
Check inflation pressure weekly during use to ensure the maximum tire life and
tread wear. The following tire wear diagnostic chart will help you pinpoint the
causes and solutions of tire wear problems.
CAUTION
Proper matching of the tire/wheel combination is essential to
proper function of your trailer running gear. Some tires may call for a
maximum inflation pressure above the rim or wheel capacity. DO NOT
EXCEED MAXIMUM INFLATION PRESSURES FOR RIMS OR WHEELS.
Catastrophic failure may result.
-76-
Tire Wear Diagnostic Chart
Wear Pattern Cause Action n Adjust pressure to
Center Wear Over Inflation particular load per tire
catalog m Adjust pressure to
Edge Wear Under Inflation particular load per tire
catalog
ffl Loss of camber or
Make sure load doesn’t
Side Wear
overloading
exceed axle rating. Align
at alignment shop • Toe Wear Incorrect toe-in Align at alignment shop
ffl Cupping Out-of-balance
Check bearing adjustment
and balance tires
~ Wheel lockup &
Avoid sudden stops when
Rat Spots
tire skidding
possible and adjust
brakes
CAUTION
Tire wear should be checked frequently. Once a wear pattern
becomes firmly established in a tire it is difficult to stop, even if the
underlying cause is corrected.
-77-

Replacement Parts/Kits
Electric Brake Magnets
Brake Size
7″x11/4″
10″ X 11/2″
10″ X 2 1/4″
10″ X 2 1/4″
12″ X 2″
12″ X 2″
12 1/4″ X 2 1/2″
12 1/4″ X 3 3/8″
Magnet Kit Number
(one magnet per kit)
K71-057-00
K71-104-00
K71-104-00
K71-125-00 (4.4K)
K71-105-00
K71-125-00 (7K)
K71-378-00 (7.2K)
K71-378-00
Seal Replacement Reference
Brake Size Hub Size Standard
7″ X 11/4″ 4 or 5 Bolt K71-301-00
10″ X 11/2″ 5 Bolt K71-302-00
10″ X 2 1/4″ 4, 5 or 6 Bolt K71-303-00
12″ X 2″** 5 Bolt Demount; K71-305-00
6 ors Bolt
12 1/4″ X 2 1/2″ 8 Bolt K71-305-00
12 1/4″ X 3 3/8″ 8 Bolt K71-305-00
• • 2.12″ diameter seal journal prior to 10/97
2.25″ diameter seal journal after 10/97
-78-
Wire
Color
White
Green
Green
Black
White
Black
Red/Black
Red/Black
Seal Part No.
Nut Torque
(Fl Lbs.)
Brake Mounting
45-70
45-70
45-70
45-70
25-50
25-50
55-80
55-80
E-Z Lube• 011
K71-301-00 N/A
K71-302-00 N/A
K71-303-00 N/A
K71-305-00 K71-386-00
K71-305-00 K71-386-00
K71-305-00 K71-386-00
Brake Shoe Replacement Kits
Brake Size
7″ X 1 1/ 4″ (2.2K)
7″ x 1 3/ 4″ {2.5K)
10″ x 1 1/2″ {3.0K)
Nev-R-Adjust• (3.0K)
10″ x 2 1/ 4″ {3.5K)
Nev-R-Adjust• (3.5K)
Free Backing (3.5K)
Com:m1 Resislant(3.5K)
4.4K
Nev-R-Adjust• ( 4.4K)
12″ x 2″ {5.2K)
6K
Nev-R-Adjust• (6 & 7K)
7K
Free Backing (7K)
Corrosion Resistant (7K)
12 1/4″ x 2 1/2″ {7.2K)
(after May of 2000)
Service Parts Only (7 2K)
(before May of 2000)
12 1/4″ X 3 3/8″ (8K)
Corrosion Resistant (8K)
12 1/4″ X 3 3/8″ (8K)
(stamped backing plate
before April 2000)
3.5K Disc
(painted caliper)
3.5K-6.0K Disc
(zinc/ aluminum caliper)
6.0K Disc
7.0K Disc
8.0K Disc
Shoe and Lining Replacement (1 Brake)
Electric Hydraulic
K71-045-00 N/A
N/A K71-466-00
K71-046-00 N/A
K71-701-00LH K71-702-00RH N/A
K71-047-00 K71-267-00
K71-681-00LH K71-682-00RH N/A
N/A K71-393-00
N/A K71-423-00
K71-672-00 N/A
K71-698-00LH K71-699-00RH N/A
K71-127-00 K71-268-00
K71-127-00 N/A
K71-675-00LH K71-676-00RH N/A
K71-127-00 K71-269-00LH K71-270-00RH
N/A K71-394-00LH K71-395-00RH
N/A K71-427-00LH K71-428-00RH
K71-497-00LH K71-496-00RH N/A
K71-410-00 N/A
K71-499-00LH K71-498-00RH K71-165-00LH K71-166-00RH
N/A K71-43 7-00LH K71-438-00RH
K71-049-00LH K71-050-00RH K71-165-00LH K71-166-00RH
N/A K71-623-00 ( 1 axle set)
N/A K71-157-00 (1 axle set)
N/A K71-629-00 (1 axle set)
N/A K71-629-00 (1 axle set)
N/A K71-629-00 ( 1 axle set)
-79-

Bearing Replacement Chart
Brake
Size
7″x11/4″
10″ X 11/2″
10″ X 11/2″
10″ X 2 1/4″
10″ X 2 1/4″
12″ X 2″
12″ X 2″
12″ X 2″*
12″ X 2″
12 1/4″ X 2 1/2″
12 1/4″ X 3 3/8″
Hub
Size
4 or5
Bolt
4 or5
Bolt
5 Bolt
4, 5,or6
Bolt
6 Bolt
6 Bolt
5 Bolt
Demount
6 Bolt
8 Bolt
8 Bolt
8 Bolt
Dexter Kit
Bearings Number
Inner K71-306-00
Outer K71-306-00
Inner K71-307-00
Outer K71-306-00
Inner K71-307-00
Outer K71-306-00
Inner K71-390-00
Outer K71-306-00
Inner K71-390-00
Outer K71-307-00
Inner K71-308-00
Outer K71-307-00
Inner K71-308-00
Outer K71-309-00
Inner K71-308-00
Outer K71-309-00
Inner K71-308-00
Outer K71-310-00
Inner K71-308-00
Outer K71-405-00
Inner K71-308-00
Outer K71-415-00
-80-
Industry Part # Axle
Cup/Cone Capacity
L44610/l44649 2K
L44610/l44649
LM67010/LM67048 2.8K
L44610/L44649
LM67010/LM67048 3K
L44610/L44649
L68111/l68149 3.5K
L44610/l44649 4K (10F)
L68111/L68149 4.4K
LM67010/LM67048
25520/25580 5.2K
LM67010/LM67048
25520/25580 7K
15245/15123
25520/25580 6K
15245/15123
25520/25580 6K, 7K
14276/14125A
25520/25580 7.2K
02420/02475
25520/25580 8K
02420/02475
Storage
Storage Preparation
If your trailer is to be stored for an extended period of time or over the winter, it
is important that the trailer be prepared properly.
1. Remove the emergency breakaway battery and store inside, out of the
weather. Charge the battery at least every 90 days.
2. Jack up the trailer and place jack stands under the trailer frame so that
the weight will be off the tires. Follow trailer manufacturer’s guidelines to
lift and support the unit. Never jack up or place jack stands on the axle
tube or on the equalizers.
&CAUTION
Do not 11ft or support the trailer on any part of the axle or suspension
system. Never go under any trailer unless It Is properly supported on
Jack stands which have been rated for the load. Improperly supported
vehicles can fall unexpectedly and cause serious Injury or death.
3. Lubricate mechanical moving parts such as the hitch, and suspension
parts, that are exposed to the weather.
4. Boat trailer axles are subject to repeated immersion. Before storing,
remove brake drums; clean, dry and re-lubricate moving brake
components; inspect bearings – clean and re-lubricate.
5. On oil lubricated hubs, the upper part of the roller bearings are not
immersed in oil and are subject to potential corrosion. For maximum
bearing life, it is recommended that you revolve your wheels periodically
(every 2-3 weeks) during periods of prolonged storage.
-81-
1=,·
DEXTER
,~· DEXTER
After Prolonged Storage
Inspection Procedure
Before removing trailer from jack stands:
1. Remove all wheels and hubs or brake drums. Note which spindle and
brake that the drum was removed from so that it can be reinstalled in
the same location.
2. Inspect suspension for wear.
3. Check tightness of hanger bolt, shackle bolt, and U-bolt nuts per
recommended torque values.
4. Check brake linings, brake drums and armature faces for excessive wear
or scoring.
5. Check brake magnets with an ohmmeter. The magnets should check 3.2
ohms. If shorted or worn excessively, they must be replaced.
6. Lubricate all brake moving parts using a high temperature brake
lubricant (LUBRIPLATE or Equivalent).
CAUTION
Do not get grease or oil on brake linings or magnet face.
7. Remove any rust from braking surface and armature surface of
drums with fine emery paper or crocus cloth. Protect bearings from
contamination while so doing.
8. Inspect oil or grease seals for wear or nicks. Replace if necessary.
9. Lubricate hub bearings. Refer to procedure in manual.
10. Reinstall hubs and adjust bearings per instructions in manual.
11. Mount and tighten wheels per instructions in manual.
-82-
Trip Preparation Checklist
There are a number of simple rules to follow in caring for your trailer axle
assembly that can add to its life and in the case of some of these rules, you
may be protecting your own life as well.
Using the following checklist before starting a trip with your trailer is highly
recommended. Some of these items should be checked 2-3 weeks prior to a
planned trip to allow sufficient time to perform maintenance.
1. Check your maintenance schedule and be sure you are up-to-date.
2. Check hitch. Is it showing wear? Is it properly lubricated?
3. Fasten safety chains and breakaway switch actuating chain securely.
Make certain the breakaway battery is fully charged.
4. Inspect towing hookup for secure attachment.
5. Load your trailer so that approximately 10% of the trailers total weight is
on the hitch. For light trailers this should be increased to 15%.
6. Do Not Overload. Stay within your gross vehicle rated capacity (consult
your trailers identification plate).
7. Inflate tires according to manufacturer’s specifications; inspect tires for
cuts, excessive wear, etc.
8. Check wheel mounting nuts/bolts with a torque wrench. Torque in proper
sequence, to the levels specified in this manual.
9. Make certain the brakes are synchronized and functioning properly.
10. Check tightness of hanger bolt, shackle bolt, and LI-bolt nuts per torque
values specified in manual.
11. Check operation of all lights.
12. Check that your trailer is towing in a level position and adjust hitch
height if required.
-83-

Item
Brakes
Brake Adjustment
Brake Magnets
Brake Linings
Brake Controller
Brake Cylinders
Brake Lines
Trailer Brake Wiring
Breakaway System
Hub/ Drum
Wheel Bearings
and Cups
Seals
Springs
Suspension Parts
Suspension Wet Bolts
& Equalizers
Extreme Duty
Bushings
Hangers
Wheel Nuts
and Bolts
Wheels
Tire Inflation Pressure
Tire Condition
Maintenance Schedule
Function Required
Test that they are operational.
Adjust to proper operating
clearance (not required with Nev-
R-Adjust’ brakes).
Inspect for wear and current draw.
Inspect for wear or contamination.
Check for correct amperage and
modulation.
Check for leaks, sticking.
Inspect for cracks, leaks, kinks.
Inspect wiring for bare spots,
fray, etc.
Check battery charge and switch
operation.
Inspect for abnormal wear or
scoring.
Inspect for corrosion or wear.
Clean and repack.
Inspect for leakage. Replace if
removed.
Inspect for wear, loss of arch.
Inspect for bending, loose
fastene,s and wear.
Grease.
Grease.
Inspect welds.
Tighten to specffied torque
values.
Inspect for cracks, dents, or
distortion •
Inflate tires to mfg’s.
specifications.
Inspect for cuts, wear, bulging,
etc.
-84-
Weekly

Dexter Axle Limited Warranty
What Products Are Covered
All Dexter Axle Company (“Dexter”) trailer axles, suspensions, and brake control
systems manufactured on or after September 1, 2016, excluding Dexter 6000
series Manufactured Housing Axles. Additional exclusions include the following
brands: UFP by Dexter, AL-KO (IAC), Titan Brakes and Actuators by Dexter, and
BrakeRite by Dexter products, which are covered under separate warranties.
Limited 1 Year Warranty
As specified in Dexter’s current publication “Operation Maintenance Service
Manual”, grease and oil seals FOR ALL PRODUCTS have a one (1) year limited
warranty to the original purchaser from the date of first sale of the trailer
incorporating such components. Except as to grease and oil seals, the
following four other warranties are available.
Limited 2 Year Warranty
Dexter warrants to the original purchaser that its electric/hydraulic brake
actuators shall be free from defects in material and workmanship for a period
of two (2) years from the date of first sale of the trailer incorporating such
components.
Limited 5 Year Warranty
Dexter warrants to the original purchaser that its axles, suspension systems
and Genuine Replacement Parts shall be free from defects in material and
workmanship for a period of five (5) years. The warranty period shall begin from
the date of the original purchase of the trailer and/or Genuine Replacement
Parts.
Limited 7 Year Warranty
Dexter warrants to the original purchaser that its Predator Series• electric brake
controllers shall be free from defects in material and workmanship for a period
of seven (7) years from the date of purchase.
Limited 10 Year Warranty
Dexter warrants to the original purchaser that the suspension components of
its Torflex• axles shall be free from defects in material and workmanship for a
period of ten (10) years from the date of first sale of the trailer incorporating
such suspension components.
Exclusive Remedy
Dexter will, at its option, repair or replace the affected components of any
defective axle, repair or replace the entire defective axle, or refund the lesser
of the original purchase price and the then-current list price of the axle or
components. In all cases, a reasonable time period must be allowed for
warranty repairs to be completed. Allowance will only be made for installation
costs specifically approved by Dexter.
-85-

What You Must Do
In order to make a claim under these warranties:
1. You must be the original purchaser of the trailer in which the sprung
suspension axles orTorflex• axles or components were originally installed.
2. You must promptly notify Dexter after detection of any defect, but in any
case within the applicable warranty period of such defect, and provide us
with the axle or applicable component serial number and any substantiation
of such defect which may include, but is not limited to, the return of part(s)
that we may reasonable request.
3. The axles, suspensions and components must have been installed and
maintained in accordance with good industry practice and any specific
Dexter recommendations, including those specified in Dexter’s current
publication “Operation Maintenance Service Manual”.
Excluslons
These warranties do not extend to and do not cover defects caused by:
1. The connecting of brake wiring to the trailer wiring or trailer wiring to the
towing vehicle wiring.
2. The attachment of the running gear to the frame.
3. Parts not supplied by Dexter.
4. Any damage whatsoever caused by or related to any alteration of the axle
including welding supplemental brackets to the axle.
5. Use of an axle on a unit other than the unit to which it was originally
mounted.
6. Normal wear and tear.
7. Improper alignment.
8. Improper installation.
9. Unreasonable use (including failure to provide reasonable and necessary
maintenance as specified in Dexter’s current publication “Operation
Maintenance Service Manual including required maintenance after
“Prolonged Storage”).
10. Improper torque values and torqueing of wheel nuts. (The proper torqueing
procedure and torque values are contained in Dexter’s current publication
“Operation Maintenance Service Manual”).
11. Cosmetic finish or corrosion.
-86-
Limitations
1. In all cases, Dexter reserves the right to fully satisfy Its obllgatlons
under the Limited Warranties by refunding the lesser of the original
purchase price and the then-current list price of the defective axle
( or, if the axle has been discontinued, of the most nearly comparable
current product).
2. Dexter reserves the right to furnish a substitute of replacement component
or product in the event an axle or any component of the axle is discontinued
or is otherwise unavailable.
3. These warranties are nontransferable.
General
THE FOREGOING WARRANTIES ARE EXCLUSIVE AND IN LIEU OF ALL OTHER
WARRANTIES EXCEPT THAT OFTITLE, WHETHER WRITTEN, ORAL OR IMPLIED,
IN FACT OR IN LAW (INCLUDING ANY WARRANTY AGAINST INFRINGEMENT OR
OF MERCHANTABILITY OR RTNESS FORA PARTICULAR PURPOSE).
These warranties give you specific legal rights, and you may also have other
rights which vary from state to state.
DEXTER HEREBY EXCLUDES INCIDENTAL AND CONSEQUENTIAL DAMAGES,
INCLUDING LOSS OFTIME, INCONVENIENCE, LOSS OF USE, TOWING FEES,
TELEPHONE CALLS, COST OF MEALS OR LODGING, FOR ANY BREACH OF ANY
EXPRESS OR IMPLIED WARRANlY.
Some states do not allow limitations on how long an implied warranty lasts, or
the exclusion or limitation if incidental or consequential damages, so the above
exclusion or limitation may not apply to you.
Inquiries regarding these warranties should be sent to:
Dexter Axle Company
P.O. Box 250
Elkhart, IN 46515
Note: Current publication “Operation Maintenance Service Manual” can be found at
www.dexteraxle.com.

Axle Identification
In the unlikely event that you should require service assistance from Dexter,
please have the lot (serial) number of the axle available when you call.
On all axles produced after April 2001, this nine digit number can be found
near the center on the rear side of the axle beam. Look for the words DEXTER
AXLE and the lot number will be located directly under the name. For easier
identification, rubbing a piece of chalk over the number may help bring out the
engraving.
Recreational Vehicle axles that have been certified for use in Canada will also
bear the letters CSA.
Dexter Online Parts Store
From magnets and seals to complete brake and hub kits, Dexter offers a complete line
of genuine replacement parts for your trailer. Most products are available in-stock and
ready to ship within 24 hours direct to you from the factory. With dedicated customer
support and quick turnaround, the Dexter Online Parts Store helps keep your trailer
going.
· Hub Components
· Brake Components
· Suspension Components
· Complete Hub Kits
· Brake Assemblies & Kits
· Brake Controllers & Actuators
Ready for Immediate Shipment
Direct to Your Door
Visit us online at www.dexteraxle.com
-89-
Dexter Video Gallery
In keeping with our continual commitment to industry safety and the development
of innovative products, please feel free to view our ongoing video gallery at www.
dexteraxle.com/resources/videos or scan the following QR codes. We are confident
these videos will help educate and promote the Dexter product line that you, as our
customer, are investing in.
Bearing
Maintenance
!Ii~ -E-Z LUBE0
System
~ -Manual Bleed
Hydraulic Disc
Removable
Spindle
a~ ~
E/ H Actuator
Installation
Genuine Brakes
Medium Duty
Axles
~~ -Sway Control
-90-
II (!I ~·.
Electric Brakes
Genuine
Replacement Parts
Nev-R-Adjust·
Brakes
m~~
TORFLEX0
Suspension Axles
•1!1~- .
E-Z FLEX”
Suspension
Leaf Spring
Axles
Power Bleed
Hydraulic Disc
Service Record
Date Service Performed Mileage
-91-
Service Record
Date Service Performed Mileage
-92-
Service Record
Date Service Performed Mileage

Genuine Dexter axles and components are available
nationwide from our plant locations listed below or
through our network of distributors. Check our web site
for the distributor nearest you.
Dexter – Pit 12
301 West Pearl Street
Fremont, Indiana 46737
Phone: 260-495-5100
Fax: 260-495-1701
Dexter – Pit 23
5600 Bucknell Drive SW
Atlanta, Georgia 30336
Phone: 404-477-6899
Fax: 470-443-1715
Dexter – Pit 51
34 7 King Street West
Ingersoll, Ontario N5C 3K6
Phone: 519-485-2210
Fax: 519-485-2163
www.lngersollaxles.com
Dexter – Headquarters
2900 Industrial Parkway East ■ Elkhart, Indiana 46516
Phone: 574-295-7888 ■ Fax: 574-295-8666
www.dexteraxle.com
Dexter – Pit 13
500 South 7th Street
Albion, Indiana 46701
Phone: 260-636-2195
Fax: 260-636-3030
Dexter – Pit 24
135 Sunshine Lane
San Marcos, California 92069
Phone: 760-744-1610
Fax: 760-744-1616
Dexter – Pit 52
5885 51 Steel SE
Calgary, Alberta T2C 3V2
Phone: 587-323-8411
Fax: 587-327-0129
Dexter – Pit 15
500 Southeast 27th Street
El Reno, Oklahoma 73036
Phone: 405-262-6700
Fax: 405-262-9089
Dexter – Pit 25
1041 Baxter Lane
Winchester, Tennessee 37398
Phone: 931-967-5101
Fax: 931-967-1828
Dexter – Pit 61
21611 Protecta Drive
Elkhart, Indiana 46516
Phone: 574-294-6651
Fax: 574-295-6626
Dexter – Pit 21
199 Perimeter Road
Monticello, Georgia 31064
Phone: 706-468-6495
Fax: 706-468-2966
Dexter – Pit 39
902 South Division Street
Bristol, Indiana 46507
Phone: 574-848-4491
Fax: 57 4-848-4825
www.ventllne.com
Dexter – Pit 62
301 North Kennedy Street
Shawnee, Oklahoma 74801
Phone: 405-273-9315
Fax: 405-273-1054
NO PART OF THIS CATALOG MAY BE REPRODUCED WITHOUT DEXTER’S PERMISSION.
ALL PART NUMBERS, DIMENSIONS AND SPECIRCATIONS IN THIS CATALOG ARE SUBJECT
TO CHANGE WITHOUT NOTICE.