BEGINNING SEPTEMBER 11, 1981, THM 125 & 125C TRANSMISSIONS WILL BE ASSEMBLED WITH A NEW PART CALLED AN OIL WEIR. THIS PART WILL BE USED FOR ONE MONTH AS A P.T.R. (PRODUCTION TRAIL RUN). THE OIL WEIR IS LOCATED IN THE REAR CASE - OIL PAN AREA AND WILL REVISE THE LUBRICATION FLOW AROUND THE DIFFERENTIAL ASSEMBLY. SEE FIGURE 1. THE OIL WEIR, PART NUMBER 8637836, IS HELD IN PLACE BY A RETAINING CLIP, PART NUMBER 8637837, AND BOTH PARTS ARE AVAILABLE FOR SERVICE. TRANSMISSIONS BUILT WITHOUT AN OIL WEIR DO NOT REQUIRE ITS ADDITION DURING SERVICE.
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.