Some confusion exists on obtaining the correct transmission end play for THM 700-R4 transmissions. The following information will be helpful to technicians when checking or setting end play.
Service Information
1. Refer to the service manual for the correct procedure to check transmission end play.
2. If end play is not within specification or cannot be brought within specification by changing the selective washer, the transmission probably is misassembled. See Figure 1.
The most common type of misassembly, which affects end play, is either omitting or incorrectly installing bearing assemblies or thrust washers. If misassembly is suspected, first check for proper installation of the bearing assembly (615) and selective thrust washer (616) shown in Figure 1. Next check for proper installation of all other bearing assemblies and thrust washers as shown in Figure 2.
Do not try to correct end play by grinding down the selective thrust washer, using two selective thrust washers, or omitting the selective thrust washer.
3. When the transmission is properly assembled, there is normal clearance between the reverse input clutch housing and drum assembly (605), and the reaction sun shell (670). This normal clearance (1.121 mm to 3.744 mm) will not affect the transmission end play. This clearance can be observed through the case opening as shown in Figure 3. Do not try to shim this clearance out of the transmission.
4. End play outside of 0.13 to 0.92 mm (.005 - .036) will cause excessive wear to all bearing assemblies, thrust washers, and their mating parts.
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.