HARSH 1-2 UPSHIFT WHEN HOT 1-2 ACCUM. FEEDBACK ORIFICE

VEHICLES AFFECTED: ALL MODELS

A 1986 THM 125C transaxle may experience a harsh 1-2 upshift when hot during medium to hard throttle acceleration. Refer to Figure 1 for transaxle identification information and to chart below for models.

When servicing this condition on a THM 125C made between the serial numbers listed below, remove the spacer plate and measure the diameter of the 1-2 accumulator feedback orifice (refer to figure 2 for location). If the hole is 1.02 mm (0.040 inch), replace the spacer plate with the indicated service spacer plate, which has a larger 3.18 mm (0.125 inch) 1-2 accumulator feedback orifice.

SERIAL NUMBER SERIAL NUMBER SPACER PLATE MODEL START END PART NUMBER

BAC 4482 6468 8660575 BDC 2137 2289 8660575 BPC 52519 57074 8660575 CAC 8054 8280 8660581 CBC 127346 128483 8660581 CCC 1914 2059 8660581 CMC 11283 11286 8660581 HXC 4215 4215 8660581 PHC 10949 12483 8660552 PKC 13015 14585 8660552 PNC 147386 162750 8660552 PRC 35775 39656 8660552 ISC 5642 6461 8660579

Refer to the appropriate Service Manual for removal and installation procedures.

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.