Assembly Procedure
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, 2004 Chevrolet Cab & Chassis Silverado, and 2003 GMC Sierra. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Do not use abrasives to clean the brake master cylinder bore.
- Clean the interior and exterior of the master cylinder, the secondary piston (1), and the return spring in denatured alcohol, or equivalent.
- Inspect the master cylinder bore, inlet and outlet ports, the secondary piston (1), and the return spring for cracks, scoring, pitting, and/or corrosion. Replace the master cylinder if any of these conditions exist.
- Dry the master cylinder and the individual components with non-lubricated, filtered air.
- Lubricate the master cylinder bore, the secondary piston (1), the return spring, and all of the individual overhaul components with Delco Supreme 11® (GM P/N 12377967) or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
- Assemble the lubricated, new primary seal (6) and retainer, and new secondary seal (5) onto the secondary piston.
- Install the lubricated return spring and secondary piston assembly (1) into the cylinder bore.
- Install the lubricated, new primary piston assembly (2) into the cylinder bore.
- Using a smooth, round-ended tool, depress the primary piston (2) and install the new piston retainer.
- Install the master cylinder reservoir to the master cylinder. Refer to Master Cylinder Reservoir Replacement .
- Install the reservoir cap and diaphragm to the reservoir.
- Install the master cylinder to the vehicle. Refer to Master Cylinder Replacement (Vacuum Boost) or Master Cylinder Replacement (Hydraulic Boost) .