REVISED PARK BRAKE CONNECTING BOLT TORQUE, NEW VALUES

SUBJECT: PARK BRAKE FASTENER TORQUE

MODELS: 1985-90 B6 SCHOOL BUSES AND C5, C6, C7 MEDIUM DUTY TRUCKS WITH ALLISON AUTOMATIC TRANSMISSIONS (MF1, ME3) AND HYDRAULIC BRAKES (JE3)

Some of the above model vehicles may experience loosening of the bolts connecting the parking brake drum to the companion flange assembly. To reme- dy this condition new torque values have been specified for the yoke and drum assembly bolts.

SERVICE PROCEDURE

1. Coat the threads of the four (4) 1/2-13 bolts with primer from the retaining compound kit.

2. After the primer has dried, coat the threads with retaining compound (Loctite) from the retaining compound kit.

3. Install drum to yoke assembly and torque the bolts to 114-143 N-m (85-103 lbs. ft.).

SERVICE PARTS INFORMATION

Part Description Quantity Number -------- ----------------------- -------- 12345493 Kit: retaining compound 1 (Loctite) and primer

Parts are currently available through GMSPO.

WARRANTY INFORMATION

For vehicles repaired under warranty use: Labor Operation: T7031 Labor Time: 1.0 hr.

NOTE: Labor Operation is coded to base vehicle coverage in the warranty system.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.