GM Service Manual Online
For 1990-2009 cars only

These tests will not find all master cylinder malfunctions. If you cannot find the cause with these tests, refer to Brake System Diagnosis.

Visual Inspection

    • Check for a cracked casting or brake fluid leaks around the master cylinder.
        A leak will have at least one drop of fluid. A damp condition is normal.
    • Check the pedal linkage for binding and for incorrect pushrod length.
        Disassemble the master cylinder if no brake pedal binding or improper brake pedal travel is found. Refer to Master Cylinder Overhaul .
    • Check the master cylinder for swollen or elongated primary piston seals.
        If you find swollen seals, refer to Brake Fluid and Brake Fluid Handling .