OIL PAN/VALVE BODY COVER LEAK NEW PAN / VALVE BODY COVER
Model and Year THM 125/125C
Beginning in September, 1983, the THM 125/125C transaxle went into production using a new oil pan and valve body cover. This new oil pan (P/N 8643574) and valve body cover (P/N 8643575) are thicker and have a raised, continuous rib on the flange (see Figure 1).
The new oil pan requires a new gasket (P/N 8643572). The new valve body cover also requires a new gasket (P/N 8631340). New hex head bolts with conical washers (P/N 8643879) are to be used with both the oil pan and valve body cover (see Figure 2).
SERVICE INFORMATION
1. If a leak occurs, refer to your service manual for diagnostic and disassembly/reassembly procedures.
2. When servicing any THM 125/125C transaxle for a leak in the oil pan or valve body cover area, visually inspect the oil pan and valve body cover bolts to determine if the new par ts have been installed (refer to Figure 2).
3. If the transaxle was built prior to September, 1983, order service package 8653942 to correct a leak in the oil pan area, or service package 8653943 to correct a leak in the valve body cover area. These packages contain:
SERVICE PACKAGE 8653942 SERVICE PACKAGE 8653943 ----------------------- ----------------------- Qty. Description P/N Qty. Description P/N ---- ----------- --- ---- ------------- --- 1 Pan, Transaxle oil 8643574 1 cover, Valve Body 8643575 1 Gasket, Transaxle oil 1 Gasket, Valve Body Pan 8643572 Cover 8631340
16 Assembly, Hex Head 11 Assembly, Hex Head screw & conical washer 8643879 Screw & Conical Washer 8643879
1 Instruction Sheet 1 Instruction Sheet
4. If the transaxle was built after September, 1983, the gasket, bolts, oil pan and/or valve body cover can be ordered separately.
5. Do not use RTV with the new transaxle oil pan or valve body cover. Oil leaks may result.
6. When assembling the oil pan or valve body cover, follow procedures outlined in your service manual. Do not use impact tool or overtorque attaching bolts. Overtorquing may result in split or cracked gaskets. Bolts should be torqued to 8-14 N.m (6-10 ft. lbs.).
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.
