GM Service Manual Online
For 1990-2009 cars only
  1. With the transmission in neutral and the front propeller shaft removed from the transmission yoke, rotate the park brake drum one full turn.
  2. The effort required to rotate the drum should remain consistant as the drum is turned.
  3. If effort is excessive inpsct for corrosion, weak springs
  4. If the effort required to rotate the drum alternates between low effort and high effort, the drum may be out-of-round and requires replacement.
  5. Rem drum
  6. Inspect for yoke deflection
  7. With the brake drum removed, clean the braking (friction) surface of the brake drum with denatured alcohol or an equivalent approved brake cleaner.
  8. Inspect the braking surface of the brake drum for the following Braking Surface Conditions:
  9. • Heavy rust and/or pitting
    • Light surface rust can be removed with an abrasive disc; heavy surface rust indicates the drum must be replaced
    • Cracks and/or heat spots
    • Excessive blueing discoloration
    • Missing balance weights
  10. If the braking surface of the brake drum exhibits one or more of the Braking Surface Conditions, the drum requires replacement.