1. If the parking brake is malfunctioning, check for the following conditions:

•	Parking brake cable sticking

•	Parking brake out of adjustment

•	Worn brake linings. Refer to Brake Shoe Inspection .

•	Grease or oil on linings. Refer to Brake Shoe Inspection .

•	Auto-adjuster malfunction. Refer to Brake Shoe Inspection .

2. Inspect the brake linings at regular intervals, and any time the wheels are removed (tire rotation, etc.).
3. Replace the shoe and lining assemblies in the axle sets if the lining thickness is worn to within 0.76 mm (1/32 in) of the shoe or rivet.

GM replacement brake lining material is recommended in order to maintain the balance between front and rear brake performance. Installation of the brake lining material having characteristics different from those of the recommended GM replacement parts can change the intended brake balance of the vehicle.