HIGH PITCHED WHINE THM325-4L PUMP DRIVE GEAR RUBBING

Models Affected: 1984 THM 325-4L BE, BJ, OE, Models

Some 1984 THK 325-4L BE, BJ and OE model transmissions built between the serial nunbers listed below, may experience a high pitched whining noise in all gear ranges as well as Park and Neutral. The noise is similar to drive link chain noise.

This noise will increase with engine R.P.M. and may be caused by the pump drive gear rubbing against the crescent in the pump body.

When servicing any BE, BJ or OE model THM 325-4L transmission for this high pitched whining noise use the following service procedure.

Service Procedure:

1. Verify the transmission serial number on the transmission being serviced with the serial numbers in the chart below.

2. If the serial number is in the range of the numbers listed in the chart then replace the pump body and gear assembly.

3. Flush the transmission cooler lines and if necessary, dissasseable and wash the transmission.

For replacenmt of the pump, order service package 8635022 which contains the pump body and gear assembly.

MODEL SERIAL NUMBERS ----- --------------- BE 1635 TO 1704 BJ 1218 TO 1247 OE 32450 TO 34286

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.