GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 21177-A Brake Drum/Shoe Clearance Gauge


    Object Number: 171482  Size: MH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Tires and Wheels. Mark the relationship of the wheel to the axle flange in order to ensure proper balance upon reassembly.
  3. Remove the brake drum. Refer to Brake Drum Replacement . Mark the relationship of the drum to the axle flange in order to ensure proper balance upon reassembly.
  4. Measure the inside diameter of the drum (1) using the J 21177-A (as shown in part A of the illustration).
  5. Turning the star wheel (as shown in part B of the illustration), adjust the diameter of the shoe and lining (2) to be 0.76 mm (0.030 in) less than the inside drum diameter for each rear wheel.
  6. Install the drums.
  7. Install the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  8. Lower the vehicle.
  9. To assure proper brake apply. Make several alternate forward and reverse stops, applying firm force to the brake pedal.