April 2012

TRACKER TECH & HOW-TO
SUPPLIER TECHNICAL INFORMATION
Drum Brake Install for Trailers

THE FOLLOWING PUBLICATION IS PROVIDED BY
TIE DOWN ENGINEERING TO PROVIDE INSTRUCTION FOR
DRUM BRAKE INSTALLATION OF THE COMPONENTS THEY
MANUFACTURE.
THE INFORMATION PROVIDED IS A RESOURCE FOR
INSTRUCTION INTENDED AS A GENERAL GUIDE FOR THIS
AND OTHER SIMILAR APPLICATIONS.
SPECIFICATIONS ARE ALWAYS SUBJECT TO CHANGE IN THE
MANUFACTURING PROCESS SO SOME PORTIONS OF THIS
GUIDE MAY NOT DIRECTLY APPLY TO CERTAIN MODELS
OR COMPONENTS.

Drum Brake
Owners Manual

Drum Brake Information
If your trailer is equipped with hydraulic drum brakes, the brakes are activated by
the surge actuator/coupler located on the front end of the trailer tongue. When the tow
vehicle stops, the trailer pushes into the tow vehicle, compressing the master cylinder
that is located inside the actuator. The master cylinder forces brake fluid to the drum
brakes. Inside each drum brake is a wheel cylinder that expands with the surge of
brake fluid, pushing the brake shoes against the inside of the brake drum.
Drum brakes must be periodically adjusted. Recommended service intervals are after
the first 500 miles and then every 1000 miles. Drum brakes also must be flushed when
submerged in salt water or towed in road conditions where salting of the roads is done
to improve driving conditions.
Many marine and trailer accessory companies offer drum brake flush kits. If you use
your trailer in these conditions, it is recommended that you install a flush kit, if your
trailer did not come equipped with the flush kit.

Model 66 Drum Brake Actuator
Part #86167

Single Axle Brake Line Kit
Part #80326

Trailer Brake Flush Kit
Part #81107

Drum Brake Installation
1. Using an adequate capacity floor or scissors jack, raise the side of the trailer.
Block the wheels opposite the side being worked on both front and rear so that the
trailer cannot roll. DO NOT rely on the jack as the only means of support.
Always support the trailer with adequate capacity support stands.
UNDER NO CIRCUMSTANCES IS THE TRAILER TO BE SUPPORTED BY THE
TONGUE JACK WHILE BEING RAISED AT THE WHEELS!
NOTE: Check under frames for brake lines BEFORE lifting. DO NOT position jack in
areas that may damage brake lines, etc.
NOTE: Tandem and tri-axle trailers should be jacked on the frame between the
wheels, or directly under the axle within 8” of the backside of the tire. B. Single axle
trailers can be lifted on the frame just behind the axle or directly under the axle
within 8” of the backside of the tire (if lifting at the axle).
2. Remove the wheels
3. Remove the dust cap.
4. If your spindle has a tang washer, pull up on the tab so you can unlock and remove
the castle nut. If you have a cotter pin, pull it out and remove the castle nut.
5. Remove the hub. It may be helpful to release tension to the brakes pads by backing
off the star adjuster.
6. Disconnect the hydraulic brake lines or the electric brake wires.
7. Remove the backing plate by removing the 4 or 5 mounting bolts holding the brake to
the brake flange. Clean the spindle and brake flange.
8. Determine which side the brakes go on. The brakes should be labeled “L” for Drivers
side & “R” for Passenger side. If the labels have been removed, simply look at the
master cylinder on top(for hydraulic brakes), the piston inside the master cylinder
will always point forward. For Electric brakes look at the magnet bracket, the curved
bracket should point forward with the open end towards the back. See next page.

2

Drum Brake Installation

Hydraulic Brake
“Left” Drivers Side

Hydraulic Brake
“Right” Passengers Side

Electric Brake
“Left” Drivers Side

Electric Brake
“Right” Passengers Side

9. Mount the brake assembly to the brake flange with the mounting bolts.
Mounting bolts should torque to _____fps.
10. Inspect the original hub. Check the seal & bearings for wear. if there is any doubt
whatsoever, go ahead and replace the seal and bearings and repack with
fresh grease.
11. Reinstall the hub. Push the hub back into place. Make sure your bearings are seated.
12. Install the washer and use a new tang washer. It is always a good idea to replace it,
just like a cotter pin.
13. Reinstall a castle nut, run it down until it stops. Rock the hub back and forth a little
bit. Spin the hub a little bit. Make sure everything is seated. Run the castle nut down
until it stops and then back off to the next notch, whichever you can use one of the
tabs on the tang washer bend it down into the castle nut.

Drum Brake Installation
14. Install the dust cap.
15. Reattach electric brake wires or follow the instructions for hydraulic bleeding.
Adjusting The Brakes
16. With trailer wheel off the ground and tire
mounted. Remove the rubber access hole
plugs from the rear of the brake
backing plate.
17. Inserting a brake spoon or flat screwdriver
through the access hole(s), tighten the star
adjuster while rotating the wheel in the
forward direction.
NOTE: Always spin wheel in the forward
direction as if the trailer was traveling
forward on the road. Tighten the star
adjuster until the wheel reaches a point
where the brake shoes start to engage.
18. Loosen the star adjustor one click at a time while turning the wheel in a forward
rotation. Continue adjusting one click at a time until the wheel rotates with
little effort.
19. Replace the rubber access hole plugs.
20. Repeat this procedure for all braking wheels.

Bleeding the Brake System - Hydraulic Drum Bakes Only
Use only DOT-3 heavy duty fluid in the actuator. Do not re-use brake fluid. Do not
use any other type of brake fluid other than DOT-3.
If pressure bleeding equipment is available, follow the manufacturer’s instructions
in bleeding the system. These types of brake bleeders are available at your local
automotive supply.
Manually Bleeding, Pumping the Actuator: Insert a heavy-duty flat blade screwdriver
into the hole provided on top of the actuator near the front. Insert the screwdriver and
catch the bleeding latch bracket and with a pumping action tilt the screwdriver front to
back in a rocking motion to activate the master cylinder in order to bleed the brakes.
To bleed master cylinder and brakes, install bleeder hose on first wheel cylinder to
be bled; if tandem axle trailer, bleed furthermost axle first, and the furthermost brake
on that axle first. Loosen the bleeder screw located in the wheel cylinder one turn, the
system is now open to the atmosphere. Attach a loose end of a hose from the bleeder
valve with the other end submerged in a glass container of brake fluid. While pumping
the actuator watch and observe the bubbling (hose must be submerged into clean brake
fluid to keep air from traveling back into the brake cylinder).
The bleeding operation for that brake is complete when bubbling stops. Be sure to
tighten bleeder screw securely.
Each wheel cylinder must be bleed until all air is out of the lines. Replenish the
brake fluid during the bleeding process so the level does not fall below half full level in
the master cylinder reservoir. When bleeding and testing is completed, make sure
master cylinder is filled the reservoir and filler cap is securely in place.
When using drum or disc brakes on tandem axle trailers, both axles must be
installed with brakes, Failure to install brakes on both axles will result in loss of
braking performance, overheating of brakes & wheel hub, and significantly reduce
brake pad life.
WARNING
Brakes should always be flushed with fresh water after using trailer in corrosive
conditions. This includes salt water, fertilizers and other corrosive materials.
Before storing trailer remove brakes and clean thoroughly. It is also wise to
repack the bearings at the same time.
WARNING
DO NOT REUSE BRAKE FLUID. Always use fresh DOT 3 fluid from a fresh
container. Failure to maintain proper levels of fluid will cause brake failure.

Electric Drum Brake Information
Electric brakes are activated by a brake controller located in the tow vehicle. This is
generally an accessory that must be purchased separately. Please research before
buying. Some controllers work better with different brand tow vehicles.
Electric drum brakes are not recommended for marine applications
Electric brakes are individually adjusted in the same way the hydraulic drum brakes
are adjusted that is covered in this manual. The electric drum brakes work by an
electrical current going to the brakes and activating a magnet. The magnet is then
attracted to the inside wall of the drum hub. This drags the magnet and pushes the
brake shoes out against the drum hub. The brake controller is generally adjustable to
regulate the amount of current given to the magnets/drum brakes. This adjustment
controls the amount of braking force applied.
Wires are connected to the brakes by one of two methods:
1. Plug in wires
2. Twist wires with a wire cap cover.
There is not a specified positive/negative connection at the brakes

Hydraulic Drum Brake Trouble Shooting
Symptoms

Possible Cause

Noise or brake chatter

Improper brake adjustment.
Brake fluid or grease on lining.
Improperly adjusted or worn wheel bearing.
Drum out of round.
Dirt on drum or lining surface.
Dust in rivet holes.
Lining glazed or worn.
Scored drum.
Loose backing plate.
Weak or broken return springs.

Only one brake is activating

Improper brake adjustment.
(see brake adjustment)
Brake line is restricted.
Improperly adjusted or worn wheel bearing.
Drum out of round.
Loose backing plate.
Faulty wheel cylinder.
Weak or broken shoe return spring.
Glazed or worn lining.
Loose lining.
Air in hydraulic system.
Dirty brake fluid.

All brakes drag

Faulty actuator.
Mechanical resistance at actuator or shoes.
Brake lines restricted.
Dirty brake fluid.
Faulty back up solenoid (if used).

Brakes do not apply

Leaks or insufficient brake fluid.
Air in hydraulic system.
Improper brake adjustment.
Faulty actuator.
Lining glazed or worn.
Brake fluid or grease on lining.
Dirty brake fluid.

Leaking wheel cylinder

Check and replace wheel cylinder and
bleed brakes.

Seized wheel cylinder piston Check and replace wheel cylinder and bleed brakes.

Return Spring

Shoe Pin
Upper Return
Spring

Adjuster Shim

Hydraulic Drum Brake Parts
Hold Down
Spring
Assembly Retainer Washer
Left Brake Pad
Dust Plugs
Return Spring (Free Backing) Wheel Cylinder Assembly
Wheel Adju
Hold Down
Rear Upper Upper Return
Spring Return Spring Spring
Lower Retu
Adjuster Shim
Assembly

Shoe Pin

Cylinder Assembly
Brake Pad
Return
eUpper
Backing)
Spring

Right Brake Pad
(Free Backing)
Wheel Adjuster Assembly
Lower Return Spring

Dust Plugs

Rear Upper
Return Spring

Shoe Pin

Hold Down
Spring
Assembly

Hold Down
Spring
Assembly

H
S
A

Left Brake Pad
(Free Backing)
Rear Upper
Return Spring

Right Brake Pad
(Free Backing)
l Adjuster Assembly
Return Spring

Actuat
Primary Pad
Hold Down
Spring
Assembly

Right BrakeHold
PadDown
(Free Backing)
Spring
Assembl
Wheel Adjuster Assembly
Lower Return Spring

Dust Plugs

ugs

Drum Wheel Cylinder Kit for
10” & 12” Brakes
includes; LH & RH Wheel Cylinder
and mounting screws

Magnet
Sprin

Part #80994

Drum Replacement Parts Kit
(Free backing & Uni-Servo) includes all parts shown,
excluding pads, back plate and wheel cylinder
10” Parts Kit
Part #81096
12” Parts Kit
Part #81095

Brake Pad Replacement Kits
Kits include brake pad sets for left and
right side brakes
7” Free backing Shoe (lining) Kit
Part #81113
10” Free backing Shoe (lining) Kit Part #81108
12” Free backing Shoe (lining) Kit Part #81109
10” Uni-Servo (lining) Kit
Part #80995
12” Uni-Servo (lining) Kit
Part #80996

Electric Drum Brake Trouble Shooting
Symptoms

Possible Cause

Noise or brake chatter

Improper brake adjustment.
Oil or grease on lining.
Improperly adjusted or worn wheel bearing.
Drum out of round.
Dirt on drum or magnet surface.
Dust in rivet holes.
Lining glazed or worn.
Scored drum.
Loose backing plate.
Weak or broken return springs.

Only one brake is activating

Improper brake adjustment. (see brake adjustment)
Improperly adjusted or worn wheel bearing.
Drum out of round.
Loose backing plate.
Weak or broken shoe return spring.
Glazed or worn lining.
Loose lining.
Bad connection at tow vehicle.
Broken or disconnected wire.
Bad magnet.
Dirt or grease inside hub surface.

All brakes drag

Faulty or improperly adjusted brake controller.
Improperly wired brake connection.
Mechanical resistance at actuator or shoes.

Brakes do not apply

Faulty brake controller.
Improperly adjusted brake controller.
Brake wires not connected to tow vehicle.
Bad Magnets.
Improper brake adjustment.
Lining glazed or worn.
Dirt or grease inside hub surface.
Damaged wiring.

Electric
Drum Brake Parts
Actuating Cam
Return Spring

Hold Down
Actuating Cam
Spring
Return Spring
ActuatingAssembly
Level
Arm
Upper Return
Primary
Spring
Actuating
Level Pad
Arm
Secondary Pad
Dust Plugs

wn

embly
Primary Pad

U
S

Brake Adjuster

gnet &
pring
Hold Down
Spring
Assembly
Actuating Cam
Upper Return
Spring

Magnet &
Spring

Hold Down
Spring
Assembly
Secondary Pad

Lower Return Spring
Hold Down
Spring
Assembly

Magnet &
Spring

Hold
Sprin
Asse

Hold Down
Spring
Assembly

Dust Plugs

S
Dust Plugs
Secondary Pad
Brake Adjust

Brake Adjuster

Lower Return

Lower Return Spring

Spring/Adjuster Replacement Kit
for 10” & 12” brakes
Part #82075

Dust Plugs
Brake Adjuster
Lower Return Spring

Magnet, Wiring & Spring Assembly
Part #82078
10” Magnet Assembly
Part #82079
12” Magnet Assembly

Pad Replacement Kits
10” Electric Shoe (lining) Kit
12” Electric Shoe (lining) Kit

Part #82076
Part #82077

TIE DOWN ENGINEERING
255 Villanova Drive SW, Atlanta, GA 30336
(404) 344-0000 • Fax (404) 349-0401
© 2011 TIE DOWN ENGINEERING, ALL RIGHTS RESERVED
Instruction Manual #08095

063011,C934

Drum Brake
Owner Manual