Parking Brake Adjustment

Special Tools 

CH-21177-A  Drum To Brake Shoe Clearance Gauge

Equivalent regional tools:Special Tools 

1. Adjustments to the parking brake shoes are not necessary after replacing the electronic parking brake control module or parking brake cable.
2. Disable the parking brake cable adjuster. Parking Brake Cable Adjuster Disabling 
3. Verify that the parking brake releases completely.
4. Raise and support the vehicle. Lifting and Jacking the Vehicle (ZL1) , or Lifting and Jacking the Vehicle (Convertible)
5. Remove the rear tire and wheel assemblies. Tire and Wheel Removal and Installation
NOTE:

Do not operate the electronic parking brake with the rear disc brake rotor(s) removed.

6. Remove the rear brake rotors. Rear Brake Rotor Replacement (J6G, J6M) , or Rear Brake Rotor Replacement (JL9, J55) , or Rear Brake Rotor Replacement (J6H)

7. Courtesy of GENERAL MOTORS COMPANY

   Set the CH-21177-A  Drum To Brake Shoe Clearance Gauge (1) inside of the parking brake drum at the widest point.

   • Place the contacts of the tool at the widest point of the parking brake drum portion of the rotor.
   • Tighten the set screw on the tool to ensure the proper measurement when removing the tool from the drum.

8. Courtesy of GENERAL MOTORS COMPANY

   Position the CH-21177-A  Drum To Brake Shoe Clearance Gauge (1) over the parking brake shoes at the widest point.

9. Turn the parking brake shoe adjuster until the parking brake shoes just contact the CH-21177-A  drum to brake shoe clearance gauge.
10. Repeat steps 8 - 10 for the opposite parking brake assembly.
11. Install the rear brake rotors. Rear Brake Rotor Replacement (J6G, J6M) , or Rear Brake Rotor Replacement (JL9, J55) , or Rear Brake Rotor Replacement (J6H)
12. Rotate the rotor and turn shoe adjuster until there slight drag then back off shoe adjuster until the rotor rotates freely.
13. Install the rear tire and wheel assemblies. Tire and Wheel Removal and Installation
14. Lower the vehicle to curb height.
15. Enable the parking brake cable adjuster. Parking Brake Cable Adjuster Enabling 
NOTE:

If the rear wheels rotate during the following test, readjust the parking brake shoes.

16. Apply the parking brake. Inspect the rotation of the rear wheels:
    • The wheels should not rotate forward.
    • The wheels should not rotate rearward.
17. Release the parking brake. Verify that the wheels rotate freely.
18. Lower the vehicle.