Parking Brake System: Service and Repair
Park Brake Hardware Replacement^ Tools Required
- J 38400 Brake Shoe Spanner and Spring Remover
Removal Procedure
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 suitably support the vehicle. Refer to Vehicle Lifting.
2. Remove the tire and the wheel.
3. Remove the brake drum.
4. Remove the return spring (1). Use the J 38400 in order to pry the loop end of the adjuster spring from the adjuster actuator. Then disengage the adjuster spring from the web of the parking brake shoe.
5. Remove the lift end of the universal spring (2) from the adjuster shoe and the lining (1).
6. Insert the hook end of the J 38400 between the universal spring and the adjuster shoe web.
7. Pull and twist the J 38400 in order to lift the end of the spring (2) out of the shoe web hole.
8. Pull the end of the universal spring (2) toward the axle with the flat edge of the J 38400 until it snaps down off the shoe web onto the backing plate.
9. Remove the adjuster actuator (1) from the following components:
^ The brake shoe
^ The brake lining (4, 5)
^ The adjusting screw (2)
10. Remove the parking brake lever (3) from the brake shoe.
11. Remove the parking brake lever from the parking brake cable.
Installation Procedure
1. Install the parking brake lever (4) to the parking brake cable (5).
2. Install the parking brake lever (4) to the brake shoe.
3. Reinstall the hooking center section of the universal spring under the tab on the anchor.
4. Install the brake shoe. Position the shoe and the lining on the backing plate.
5. Use the J 38400 in order to pull up the end of the universal spring (2), resting the return spring on the web of the brake shoe (1).
6. Use the J 38400 in order to pull the end of the universal spring over until it snaps in the slot in the brake shoe.
7. Before reinstallation, disassemble, 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.
^ Apply GM P/N 1052196 or equivalent brake lubricant to the following areas:
- The adjuster screw threads
- The inside the diameter of the adjuster socket
- The socket face
- 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
8. Inspect the threads of the adjuster screw for smooth rotation over the full length.
9. Install the adjusting screw assembly (2):
9.1. Engage the adjuster nut end of the adjusting screw (2) with the web of the brake shoe and lining and the parking brake lever (3).
9.2. Position the adjuster shoe and lining so that the shoe web engages the deep slot in the socket end of the adjusting screw.
10. Install the return spring into the adjuster shoe and lining.
10.1. Use the J 38400 in order to pull up the end of the return spring, resting the return spring on the web of the brake shoe.
10.2. 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.
11. Inspect the following items in order to ensure the proper positioning and function of the adjuster actuator and the return spring:
^ 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 in a downward angle
^ Use the J 38400 between the upper ends of the shoe and lining assemblies. Spread the shoes apart and verify proper rotation of the star wheel.
12. Adjust the drum brakes.
13. Adjust the parking brake.
14. Install the tires and the wheels.
15. Lower the vehicle.