Brake Shoe: Service and Repair

REMOVAL PROCEDURE

^ Tools Required
- J 38400 Brake Shoe Spanner and Spring Remover

Caution: Keep fingers away from rear brake shoe springs to prevent fingers from being pinched between spring and shoe web or spring and backing plate.

Notice: Do not pry against the splash shield or backing plate in attempt to free the drum. This will bend the splash shield or backing plate. A bent backing plate may cause brake chatter and/or pulsation.

Notice: Do not over stretch the Adjuster spring. Damage can occur if the spring is over stretched.

1. Raise and support the vehicle.
2. Mark (index) the relationship of the wheel to the axle flange.
3. Remove the tire and wheel assembly.
4. Index the relationship of the drum to the axle flange.
5. Remove the brake drum.





6. Remove the adjuster spring (1).
^ Use the J 38400 in order to pry the loop end of the adjuster spring from the adjuster actuator.
^ Disengage the adjuster spring from the web of the parking brake shoe.





7. Remove the lift end of the return spring (2) from the adjuster shoe and the lining (1).
8. Insert the hook end of the J 38400 between the return spring and the adjuster shoe web.





9. Pry or twist the J 38400 in order to lift the end of the spring (2) out of the shoe web hole.





10. Pry the end of the return spring (2) toward the axle with the flat edge of the J 38400 until the return spring snaps down off the shoe web onto the backing plate.





11. Remove the adjuster actuator (1) from the following components:
^ The brake shoe
^ The brake lining (4,5)
^ The adjusting screw (2)

12. Remove the parking brake lever (3) from the parking brake shoe and the parking brake lining. Do not remove the parking brake cable from the parking brake lever unless the parking brake lever is being replaced.





13. Lift the end of the return spring (2) from the parking brake shoe and the parking brake lining (1). Insert the hook end of the J 38400 between the return spring and the parking brake shoe web. Pry or twist the J 38400 in order to lift the end of the spring out of the shoe web hole.





14. Pry the end of the return spring (2) toward the axle with the flat edge of the J 38400 until the spring snaps down off the shoe web onto the backing plate.
15. Remove the parking brake shoe and the parking brake lining.
16. Remove the return spring from the backing plate. If only the shoes and linings are being replaced, do not remove the return spring.
17. Clean all parts in clean denatured alcohol.
18. Inspect and replace any parts that are of doubtful strength or quality due to the following conditions:
^ Discoloration from heat
^ Over stress
^ The parts are worn

19. Inspect the wheel cylinder for the following conditions:
^ Leakage
^ Cut or damaged boots

20. If the above conditions are found, repair or replace the wheel cylinder as necessary.

INSTALLATION PROCEDURE

Important: Lubricate the following components with GM P/N 1052196 or equivalent brake lubricant:
^ The 6 raised shoe pads on the backing plate
^ The anchor surfaces on the backing plate. The anchor surfaces contact the lower ends of the brake shoes.





1. Reinstall the hooking center spring section under the tab on the anchor, if the return spring was removed.
2. Install the parking brake shoe and the lining. Position the shoe and the lining on the backing plate.
3. Use the J 38400 in order to pull up the end of the return spring (2), resting the return spring on the web of the brake shoe (1).
4. Use the J 38400 in order to pull the end of the return spring over until the return spring snaps in the slot in the brake shoe.





5. Connect the parking brake lever (3) to the parking brake shoe and lining (4).
6. Connect the parking brake cable to the parking brake lever, if disconnected.
7. Before reinstallation, disassemble and thoroughly clean and lubricate the adjusting screw (2) in the following manner:
^ Clean the adjuster screw threads with a wire brush.
^ Wash all components in clean denatured alcohol.
^ Adequate lubrication is achieved when a continuous bead of lubricant is on the end of the adjuster nut and the socket when the threads are fully engaged
Apply GM P/N 1052196 or an equivalent brake lubricant to the following areas:
- The adjuster screw threads
- The inside diameter of the adjuster socket
- The socket face

8. Inspect the threads of the adjuster screw for smooth rotation over the full length of the screw.





9. Install the following components:
^ The adjusting screw (2)
^ The adjuster shoe
^ The adjuster shoe lining

10. Engage the adjuster nut end of the adjusting screw (2) with the web of the parking brake shoe and lining and the parking brake lever (3).
11. Position the adjuster shoe and the lining so that the shoe web engages the deep slot in the socket end of the adjusting screw.
12. Install the return spring into the adjuster shoe and the lining.
12.1. Use the J 38400 in order to pull up the end of the return spring. Rest the return spring on the web of the brake shoe.
12.2. Use the J 38400 in order to pull the end of the return spring over until the return spring snaps into the slot in the brake shoe.





13. Install the adjuster actuator:
13.1. Lubricate the tab and the pivot point on the adjuster lever with GM P/N 1052196 or an equivalent brake lubricant.
13.2. Use the J 38400 in order to spread the brake shoes while working the adjuster actuator (1) into position.

14. Install the adjuster spring.
14.1. Engage the U-shaped end of the spring in the hole in the web of the parking brake shoe.
14.2. Use the J 38400 in order to stretch the spring and engage the loop end over the tab on the adjuster actuator.





15. Note the following items in order to ensure the proper positioning and function of the adjuster actuator:
^ The adjuster actuator pivots in the shoe web slot.
^ The notch in the adjuster actuator rests on the step in the adjusting screw (2) notch.
^ The arm of the adjuster actuator rests freely on the star wheel teeth of the adjuster screw, not trapped under the teeth at a downward angle.
^ Use the J 38400 between the upper ends of the shoe and lining assemblies. Spread the shoes apart and watch for proper rotation of the star wheel.

16. Adjust the brakes.
17. Adjust the parking brake.
18. Install the brake drums. Align the index marks made during removal.
19. Install the tire and wheel assembly. Align the marks made during removal.
20. Lower the vehicle.