A/C NOISE OR VIBRATION WITH A/C ON (INSTALL KIT)

AIR CONDITIONING NOISE/VIBRATION

Vehicles Affected: 1988 C/K TRUCKS WITH AIR CONDITIONING AND 4.3L, 5.0L AND 5.7L ENGINES (VIN CODES Z, H, AND K)

Some 1988 C/K trucks with 4.3L, 5.0L and 5.7L engines may exhibit noise/vibration when the air conditioning is engaged. This noise/vibration is the result of a resonance set up in the serpentine accessory drive system with air conditioning on. If his condition is experienced on 1988 C/K trucks built before the VIN breakpoints listed below, install the following kits. Installation instructions are included with the kits.

Part Number Engine ----------- ------ 10085731 4.3L V-6 With A/C

10085730 5.0L/5.7L V-8 With A/C

All 1988 C/K trucks built after the following VIN breakpoints, last 7 digits) have had the above kits installed at the assembly plants.

Oshawa # 2 Chevrolet 1178198 GMC 1528693 Fort Wayne Chevrolet Z158598 GMC Z517538 Pontiac East Chevrolet E142329 GMC E514147

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.