GM Service Manual Online
For 1990-2009 cars only

Object Number: 177373  Size: SH

The reservoir and cap are made of plastic. The cap screws onto the top of the reservoir. Brake lining wear will cause the fluid level in the master cylinder reservoir to drop from the MAX to the MIN mark. Fluid should not be below the MIN mark or above the MAX mark. Brake fluid should not need to be added. Lining replacement will raise the brake fluid level. This ensures adequate reserve brake fluid and prevents air from entering the hydraulic system. Do not over fill the reservoir. An over filled reservoir will not allow the needed brake fluid expansion caused by heat absorbed from the brakes and the engine.

Master Cylinder Identification

Identifying information is stamped into the front surface of the body of the master cylinder.

The Delphi master cylinder has the following information:

    • The first two digits identify the build code.
    • The third digit indicates the year the master cylinder was built (Example: 7 means 1997).
    • The last digits indicate the day the master cylinder was built (Example: 271 means the 271st day of the production year).