Hubs/Drums/Bearings

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-

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
Nut Retainer

"D" Washer
Nut

E-Z Lube® Lubrication
The procedure is as follows:
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-

Hubs/Drums/Bearings

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.)

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.
Inner Bearing
Rubber Plug
Outer Bearing

Grease
Flow

Grease Fitting
Spring Loaded
Double Lip Seal

Hubs/Drums/Bearings

Metal End Cap

-58-

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-

Hubs/Drums/Bearings

Nev-R-Lube® Drums/Bearings

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.

Hubs/Drums/Bearings

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-

Hubs/Drums/Bearings

!

Resultant Tilt Value
Bearing Size
35 MM
42 MM
50 MM

End Play
.005" axial
.006" axial
.008" axial

.003" / per inch
.005" / per inch
.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.

Hubs/Drums/Bearings

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-

Hydraulic
Press

Bearing

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-

Hubs/Drums/Bearings

5. Install “internal” snap ring into hub.

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.

Axle Installation

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-

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.
Center Hanger
Shackle Link
Front
Hanger

U-Bolt
Tie Plate
Equalizer

Rear
Hanger

Shackle Bolts

Underslung Shown

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-

Suspensions

Suspension Systems

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.

Slipper Leaf Springs
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

Front
Hanger

Center Hanger

Tie Plate

Tie Plate

U-Bolt

Spring Eye Bolts

U-Bolt

Rear
Hanger

Keeper Bolts

Suspensions

Overslung Shown

The articulation of this suspension occurs when the rear end of each slipper
spring slides against the wear surfaces provided in the rear hangers or
equalizers. This suspension is also available in single and multiple axle
configurations.

-66-

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
Item

Min

Torque (Ft. Lbs.)

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
30
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-

Suspensions

Inspection and Replacement

!

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. 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 installing 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.

Suspensions

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-

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.

Torflex® 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
Mounting Bracket
Axle Tube
bar surrounded by four natural
rubber cords encased in the
main structural member of the
axle beam.
Spindle
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

Torsion Bar
Torsion Arm

-69-

Suspensions

1. With both axles blocked up, remove the spring eye bolt, shackle bolt, and
equalizer bolt from the equalizer to be repaired or replaced.

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 TORFLEX® BEAM. It has rubber cords inside and
the heat generated by welding could damage the cords.

Airflex® Suspension
The Dexter Airflex® suspension is a unique combination of Torflex® 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