You can start backing plate replacement by first supporting and raising your vehicle before placing a drain pan underneath the rear axle housing. Drain the oil from the rear axle housing by removing its oil filler plug and its Drain Plug . Start by taking out the
Brake Drum followed by removing both the wheel and tire assemblies from the back. Use a socket wrench to remove the 4 nuts at positions 4 and 6 from the rear
Axle Shaft bearing retainer studs. First disconnect the abs
Wheel Speed Sensor when replacing the backing plate. Move the sensor off to the side of the work area. The j34866 rear Axle Shaft remover (J34866) and j2619-01 slide hammer (J2619-01) should be used to extract the rear Axle Shaft and bearing from the rear axle housing. The next step involves removing both
Brake Shoes together with
Wheel Cylinder devices. Use a wrench to compress the stopper ring until the park brake cable breaks free from the backing plate. Separate the backing plate from the rear axle housing. Wash the mating surfaces between the rear Axle Shaft housing and rear Axle Shaft bearing retainer. Apply general motors sealer, gm p/n 1052366 or equivalent to the rear axle housing mating surface before installing the new backing plate while properly aligning its stud holes for retainer bolts to the rear Axle Shaft. Install the park brake cable followed by the Wheel Cylinder and finally the brake shoes. Use gm p/n 1052366 general motors sealer or equivalent on the rear Axle Shaft bearing retainer mating surface. Place the rear Axle Shaft with the bearing inside the rear axle housing while making sure the bearing demonstrates full seat engagement. Tighten the four rear Axle Shaft retaining nuts (4, 6) to 23 nm (17 ft. Lbs.) to maintain the shaft within the rear axle housing. Install the Brake Drum followed by reinstalling the Wheel Speed Sensor only if present. The rear axle housing Drain Plug requires teflon pipe sealant, gm p/n 12346004, or equivalent before installation for torque to 25 nm (18 ft. Lbs.). Use 2.2 liters (4.6 pints) of 80w-90 gl5 lubricant gm p/n 12345977 or equivalent to fill the rear axle housing until it reaches the bottom of the filler plug hole. Finally, install the filler plug and tighten it to 43 nm (32 ft. Lbs.)lower the vehicle while you remove the drain pan before the process terminates.