ON CERTAIN MEDIUM AND HEAVY DUTY TRUCKS BUILT WITH DRIVELINE PARKING BRAKE CODES 04GAR, THE PARKING BRAKE ASSEMBLY MAY NOT HOLD THE VEHICLE IN POSITION WHEN SET. FACTORS CONTRIBUTING TO THIS POSSIBILITY ARE AS FOLLOWS: (1) CRACKED OR BROKEN CAMS; (2) LOOSE OR BROKEN ANCHOR BOLTS; (3) INITIAL SHOE DIAMETER NOT SET PROPERLY DURING ASSEMBLY, WHICH CAN LEAD TO PROGRESSIVE COMPONENT DAMAGE; (4) BENT ADJUSTER LEVERS THAT CANNOT FUNCTION; OR (5) AUTOMATIC ADJUSTER CABLES THAT ARE DISCONNECTED.