Master Cylinder Replacement
Master Cylinder Replacement
Removal Procedure
1. Apply the brake pedal at least 5 times in order to exhaust the vacuum in the brake booster.
2. Remove the front suspension support brace.
3. Clean the following components:
^ The brake fluid reservoir cap
^ The brake fluid reservoir
^ The master cylinder (5)
^ The brake pipes (3,4) around the master cylinder
4. Use a flat-bladed tool in order to lift the connector security clip on the brake fluid level switch connector.
5. Disconnect the brake fluid level switch connector.
6. Place a container below the master cylinder in order to catch the brake fluid.
7. Remove the reservoir cap.
8. Remove the cap seal.
9. Caution: Refer to Brake Fluid Irritant Caution in Service Precautions.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service Precautions.
Remove the brake fluid with the syringe.
10. Loosen the 2 flare nuts and separate the 2 brake pipes from the master cylinder.
11. Install caps or plugs to the brake pipes in order to prevent brake fluid loss and contamination.
12. Install caps or plugs to the master cylinder ports in order to prevent contamination.
13. Remove the 2 nuts (8,9) from the bracket (10).
14. Remove the bolt (7) and the washer (6) from the bracket.
15. If the vehicle has a manual transmission, use a tie strap, or equivalent, in order to secure the bracket and the clutch fluid reservoir in an upright position.
16. If the vehicle has an automatic transmission, remove the bracket.
17. Remove the 2 nuts (1,2) from the master cylinder.
18. Important: Do not push the booster push rod or the brake pedal.
Remove the master cylinder assembly (4).
19. Remove and discard the O-ring (3).
20. Remove the reservoir and the reservoir seals, if necessary.
Installation Procedure
1. Install the reservoir and the reservoir seals, if necessary.
2. Install a NEW O-ring (3) to the master cylinder (4).
3. Install the master cylinder assembly to the vacuum brake booster.
4. Notice: Refer to Fastener Notice in Service Precautions.
Install the 2 nuts (1,2) to the booster studs.
Tighten the nuts to 10 Nm (88.5 inch lbs.).
5. If the vehicle has a manual transmission, remove the tie strap, or equivalent, and place the clutch fluid reservoir in the correct position.
6. Install the bracket (10).
7. Install the washer (6) and the bolt (7) to the bracket.
Tighten the bolt to 10 Nm (88.5 inch lbs.).
8. Install the 2 nuts (8,9) to the bracket.
Tighten the nuts to 8 Nm (70.8 inch lbs.).
9. Place a container under the master cylinder in order to catch the brake fluid.
10. Remove the caps or the plugs from the brake pipes and the master cylinder.
11. Push the 2 brake pipes (3,4) into the master cylinder ports.
12. Caution: Refer to Brake Fluid Caution - DOT 4 in Service Precautions.
Notice: When adding fluid to the brake fluid reservoir or to the clutch fluid reservoir, use only GM Vehicle Care Brake and Clutch Fluid Super DOT-4, GM P/N 88958860 (Canadian P/N 88901244), or equivalent DOT-4 brake fluid from a clean, sealed container. This polyglycol brake fluid is hygroscopic and absorbs moisture. Do not use fluid from an open container that may be contaminated with water. Improper or contaminated fluid could result in damage to the system components.
Important: Ensure the brake fluid level stays above half-full.
Fill the reservoir with GM Vehicle Care Brake and Clutch Fluid, GM P/N 88958860, or the equivalent DOT-4 brake fluid.
13. Allow the fluid to drip from the ports for approximately 1 minute.
14. Tighten the 2 flare nuts.
Tighten the 2 flare nuts to 14 Nm (10 ft. lbs.).
15. Bleed the brakes.
16. Fill the reservoir.
17. Install the cap seal.
18. Install the cap.
19. Remove the container from below the master cylinder.
20. Connect the brake fluid level switch connector.
21. Install the connector security clip on the brake fluid level switch connector.
22. Install the front suspension support brace.