GM 20990071
Drive Shaft

The first process to change a rear propeller shaft into an mx7 or mn6 begins by elevating and supporting the vehicle. First detach the rear Muffler together with the floor pan mid tunnel insulation. The propeller shaft needs temporary support through a suitable jack stand placed at the center support bearing before removing its mounting bolts. The propeller shaft coupler should not disconnect from its shaft during the bolt removal process which connects the coupler to the differential flange. Use proper maintenance procedures to separate the propeller shaft nuts, bolts and washers while changing out all faulty or worn-out elements. Use a flat-bladed screwdriver to remove the propeller shaft from the transmission/transfer case flange after detaching all bolts from its CV Joint at the transmission/transfer case flange. To proceed with removal, first uninstall the propeller shaft from the rear differential flange before taking it out of the vehicle. When installing the shaft users need to apply gm p/n 1051344 (Canadian P/N 993037) lubricant to its center bushing and differential flange pilot shaft. A helper should guide the propeller shaft installation before adding the center support bearing together with any necessary shims when available. The installation of mounting bolts to the center support bearing requires torque to 50 nm (37 lb ft) with the propeller shaft and drive flange dots in alignment to avoid vibrations. Clean the threads on propeller shaft-to-flange nuts along with bolts with denatured alcohol and then apply threadlocker gm p/n 12345493 (Canadian P/N 10953488) to let the compound cure for approximately ten minutes. The procedure begins with differential flange installation of the propeller shaft coupler then adds the bolt and washer before torquing the nuts that attach the coupler-to-differential flange to 85 nm (63 lb ft). The installation process requires the floor pan mid tunnel insulator and exhaust system reinstallation with proper vehicle lowering procedures after tightening the propeller shaft CV Joint to transfer case flange bolts in sequence (1-6) to 40 nm (29 lb ft).

The first step to replace front propeller shaft in an awd vehicle starts with vehicle elevation and support. Remove the lower engine shield and the right Catalytic Converter and front drive axle heat shield while taking notes about the propeller shaft position relative to the transfer case flanges and front drive axle. Start by untightening the transfer case drive flange front propeller mounting bolts and their corresponding locks followed by the detachments of front drive axle front propeller mounting bolts and their locks from the front drive axle. The front propeller shaft detachment requires a flat-bladed screwdriver to separate it from both transfer case and front drive axle drive flanges before removing the shaft from the vehicle. To install the propeller shaft maintain proper cone positioning inside the drive flanges after ensuring the reference marks on the shaft match correctly with both transfer case and front drive axle drives. Drive the propeller shaft into first the front drive axle flange followed by the transfer case drive flange. Tighten mounting bolts and locks of the front drive axle flange first then the mounting bolts and locks of the rear drive axle flange in sequence to a torque of 40 n.m (29 lb ft). The repair work requires reinstalling the front drive axle heat shield along with the right Catalytic Converter and lower engine shield before the support is removed and the vehicle is lowered.

Remove the propeller shaft coupler-to-transmission flange bolts and the propeller shaft to rear differential flange.

Raise and support the vehicle and remove the lower engine shield.

The location of the propeller shaft CV joint to the transfer case flange.