Chevrolet Sonic Repair Manual: Rear Brake Cylinder Overhaul

Disassembly Procedure

Warning:

Refer to Brake Dust Warning.

Warning:

Refer to Brake Fluid Irritant Warning.

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
2. Remove the rear brake cylinder. Refer to Rear Brake Cylinder Replacement.



3. Remove and discard the brake cylinder dust seals (1).


4. Remove the brake cylinder pistons (1) and spring (2).
5. Remove and discard the brake cylinder piston seals.
6. Inspect the brake cylinder bore for excessive corrosion, scoring, nicks, and pitting.
7. If the brake cylinder bore exhibits the above conditions, the brake cylinder assembly requires replacement.
8. Remove light corrosion in the cylinder bore with a fine crocus cloth.
9. Thoroughly clean the brake cylinder and pistons with denatured alcohol and dry with filtered, non-lubricated compressed air.

Assembly Procedure

1. Lightly lubricate the new piston seals and brake cylinder bore with GM approved brake fluid from a clean, sealed, brake fluid container.
2. Assemble the new piston seals with the lip of the seals facing inward to the brake cylinder pistons.


3. Install the brake cylinder pistons (1) and spring (2) into the brake cylinder bore.



Note:

Do not lubricate the brake cylinder dust seals.

4. Install the new brake cylinder dust seals (1).
5. Install the rear brake cylinder. Refer to Rear Brake Cylinder Replacement.
6. Bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding.