RATTLE TYPE NOISE FROM REAR OF ENGINE - NEW DAMPENER P/N

Models Affected: 1988-90 BONNEVILLE MODELS WITH 3800 V.6 ENGINE

A "tinny" rattling noise may be heard at the rear of the engine (hot engine) between idle and 1500 rpm's. This type of noise can sometimes be corrected by installing a larger timing chain dampener.

The dampener, part number 25535668, went into production engines used in Bonneville models on January 2, 1990. The date the engine was built can be found on a sticker on the rear valve cover and can be viewed by looking past the brake master cylinder from the driver's side of the car.

Parts are currently available from GMSPO.

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.