HIGH PITCH WHINE NOISE 1ST,2ND & REVERSE-1983 MODEL 200C/200R

Some 1983 THM 200C and 200-4R transmissions may experience a noise condition that sounds like a high pitched whine. This noise condition may be coming from the front internal gear assembly, and should not be confused with a torque converter bearing noise or a pump cavitation noise.

In diagnosing this condition, if the noise is noticeable in drive with the brake applied and the engine at approximately 1,500 RPM, the cause could be a torque converter bearing noise or an oil pump cavitation noise. If the whine noise is noticeable when driving the car in first, second and reverse only, the cause could be the front internal gear.

When servicing any 1983 THM 200C or 200-4R transmission for this whine noise condition and the cause has been diagnosed to be the front internal gear, replace it with P/N 8630909.

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.