Flushing the brake hydraulic system involves opening the bleeder valves at the calipers. Run new brake fluid through the system until the fluid comes out clear in color. Use Delco Supreme 11® Brake Fluid,GM P/N 12377967 or an equivalent DOT-3 motor vehicle brake fluid.
Flush the system under the following conditions:
| • | Installing new hydraulic parts |
| • | Possibility of contamination |
| • | The wrong grade of fluid in the system |
| • | The fluid contains mineral oil |
Notice: Do not use alcohol for flushing the system or cleaning assemblies where alcohol could be trapped and contaminate the brake fluid. The contaminated fluid can then cause the failure of the rubber components in the system.
Flush at each bleeder valve. Flushing is similar to the bleeding procedure. The difference is that the bleeder valve is opened 1-1/2 turns. Fluid is forced through the lines and the bleeder valves until the fluid comes out clear in color. Refer to Hydraulic Brake System Bleeding .
Inspect the master cylinder fluid level after flushing each valve.
Refill the master cylinder fluid as required. Ensure that the master cylinder reservoir is filled to the proper level after flushing. Refer to Master Cylinder Reservoir Filling .
