Chevrolet Silverado / GMC Sierra. Service manual — part 1515

13. Clean the bleeder valve, the caliper bores, the caliper passages and the pistons with

denatured alcohol. Dry the parts and blow out the brake fluid passages using filtered, non-
lubricated compressed air.

14. Replace the pistons or the caliper if any of the following conditions exist:

Scoring in the caliper bores

Corrosion in the caliper bores

Pitting in the caliper bores

Damage to the pistons (phenolic)

15. Clean the brake caliper assembly with denatured alcohol.

16. Dry with filtered, non-lubricated compressed air.

Assembly Procedure

1. Apply a small amount of clean DOT-3 brake fluid to the piston, piston seal, and piston bore.

IMPORTANT: When applying the clean brake fluid to the piston bores,

piston seals and pistons, only apply the brake fluid to one
bore at a time. This is done to ensure that the brake caliper,
seals and pistons DO NOT become contaminated with dirt or
other foreign material.

2008 Chevrolet Silverado 1500

2008 BRAKES Disc Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 24: View Of Brake Caliper Piston Seal
Courtesy of GENERAL MOTORS CORP.

2. Install the square-cut piston seal in the brake caliper bore groove.

3. Ensure that the square-cut piston seal is not twisted.

2008 Chevrolet Silverado 1500

2008 BRAKES Disc Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 25: View Of Piston Dust Seal
Courtesy of GENERAL MOTORS CORP.

4. Install the boot over the end of the piston so that the fold will face toward the brake caliper

housing piston bore opening.

2008 Chevrolet Silverado 1500

2008 BRAKES Disc Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 26: Installing Piston To Brake Caliper
Courtesy of GENERAL MOTORS CORP.

5. Position the piston to the brake caliper bore and seat the boot into the brake caliper bore

groove.

IMPORTANT: Position the piston in the bore so that it is straight and level.

2008 Chevrolet Silverado 1500

2008 BRAKES Disc Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado