AIR CONDITIONING NOISE/VIBRATION
Some 1987-88 S/T Trucks equipped with 2.8L engines may exhibit a noise/vibration when the air conditioning compressor is engaged. The noise/vibration is the result of a resonance set up in the serpentine accessory drive system with air conditioning on.
If this condition is encountered on 1987-88 S/T trucks with 2.8L engines and A/C, brace kit P/N 10115893 should be installed according to the instructions included with the kit.
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.