Wheel Cylinder: Service and Repair

Removal Procedure

1. Raise and support the vehicle. Refer to Vehicle Lifting.
2. Remove the rear tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Wheels, Tires and Alignment.
3. Remove the brake drum. Refer to Brake Drum Replacement.
4. Remove the brake shoes. Refer to Brake Shoe Replacement.
5. Clean the wheel cylinder and the outboard side of the brake backing plate. Use GM Non-Chlorinated Brake Parts Cleaner, GM P/N 12377981, or equivalent.





6. Clean the brake pipe (2) and the inboard side of the brake backing plate. Use GM Non-Chlorinated Brake Parts Cleaner, GM P/N 12377981, or equivalent.
7. If you are servicing the right wheel cylinder, loosen the 2 brake pipe flare nuts. Ensure the brake fluid does not leak from the brake pipes.
8. If you are servicing the left wheel cylinder, loosen the brake pipe flare nut (7). Ensure the brake fluid does not leak from the brake pipe.
9. Remove the 2 wheel cylinder bolts (13.
10. Remove the bleeder valve cap (3) from the left rear brake bleeder valve.
11. If you are servicing the right wheel cylinder, remove the bleeder valve cap from a front brake bleeder valve.
12. If you are servicing the right wheel cylinder, remove the 2 brake pipes from the right wheel cylinder. Plug the brake pipes with the bleeder valve caps in order to prevent contamination of the brake fluid.
13. If you are servicing the left wheel cylinder, remove the brake pipe from the left wheel cylinder. Plug the brake pipe with the bleeder valve cap.
14. Remove the wheel cylinder from the backing plate.
15. Remove the gasket from the wheel cylinder.


Installation Procedure

Important: If the gasket is worn or damaged, install a new gasket.





1. Install the gasket (2) to the wheel cylinder (1).
2. Install the wheel cylinder to the backing plate.





Notice: Refer to Fastener Notice in Service Precautions.

3. Install the 2 wheel cylinder nuts (1).
^ Tighten the nuts to 8.5 Nm (78 inch lbs.).
4. If you are installing the right wheel cylinder, remove the 2 caps from the 2 brake pipes. Install the 2 brake pipes to the wheel cylinder.
^ Tighten the 2 flare nuts to 16 Nm (12 ft. lbs.).
5. If you are installing the left wheel cylinder, remove the cap from the brake pipe.
6. Install the brake pipe (2) to the wheel cylinder.
^ Tighten the flare nut to 16 Nm (12 ft. lbs.).
If you are servicing the right wheel cylinder, install the cap to the front brake bleeder valve.
7. Install the cap (3) to the left rear brake bleeder valve.
8. Install the brake shoes. Refer to Brake Shoe Replacement.
9. Install the brake drum. Refer to Brake Drum Replacement.
10. Install the rear tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Wheels, Tires and Alignment.
11. Lower the vehicle.
12. Bleed the brake system. Refer to Hydraulic Brake System Bleeding.