GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 21177-A Drum-to-Brake Shoe Clearance Gauge

  1. Release the park brake.
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the tire and wheel. Refer to Wheel Removal in Tires and Wheels.
  4. Remove the brake drum. Refer to Brake Drum Replacement .
  5. Ensure that the stops on both of the park brake lever is against the brake shoe edges. If the parking brake cable is holding the stops off the edge of the brake shoe, adjust the park brake cable. Refer to Park Brake Cable Service/Adjustment .

  6. Object Number: 239094  Size: SH
  7. Use the J 21177-A in order to measure the drum inside diameter.

  8. Object Number: 239090  Size: SH
  9. Rotate the adjuster wheel and use the J 21177-A in order to adjust the brake shoe diameter to 1.27 mm (0.05 in) less than the drum inside diameter measurement.
  10. Install the brake drum. Refer to Brake Drum Replacement .
  11. Apply and release the brake pedal 30-35 times with a one second pause between each brake application.
  12. Install the tire and wheel. Refer to Wheel Installation in Tires and Wheels.
  13. Lower the vehicle.