All 1986 THM 700-R4 transmissions, beginning April 29, 1986, or Julian Date 119 (Refer Figure 1), are built using a new pump to case bolt and O-ring assembly. The new bolt and O-ring assembly improves sealing and bolt torque retention.
If a leak or low bolt torque retention conditiun is experienced the new pump to case bolt and O-ring (refer to Figure 2) can be ordered for service as an assembly, Service Part Number 8654343, or the O-ring can be ordered separately, Service Part Number 8654341.
Refer to the appropriate Service Manual for bolt torque specifications, which are the same for both types of bolts.
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.