Final Drive, Replacing
Final drive, replacing
Special tools:
998 5972 JACK 998 5972 Jack
999 5743 Counterhold 999 5743 Counterhold
Note! As the illustrations in this service information are used for different model years and / or models, some variation may occur. However, the essential information is always correct.
Removal
Preparations
Note! Check that the parking brake is not applied and that the gear selector is in position P.
Removing the rear wheels and the drive shaft screw
Remove:
- the rear wheels
- the screw for the drive shaft and wheel hub on both sides.
Removing the rear section of the exhaust system
Raise the vehicle.
Support the front section of the exhaust system so that there is no strain on the exhaust manifold.
Remove:
- the rear exhaust system assembly
- the mountings for the exhaust system from the rear axle member.
Removing the propeller shaft
Mark the position of the joint on the flange.
Remove the screws from the joint. Use counterhold 999 5743 Counterhold 999 5743 Counterhold.
Leave one screw in place by a few threads for safety.
Remove the screws from the support for the center bearing for the propeller shaft.
Slacken off the screws in the support for the center bearing on the right-hand side a few turns. Fully remove the screws on the left-hand side
Let the center support hang down so that the propeller shaft can be angled.
Remove the screw from the joint.
Press the shaft joints together. Remove the shaft from the carrier plate. Move the shaft to one side.
Tie up the shaft.
Removing shock absorbers, torque rods and anti-roll bar links (both sides)
Remove:
- the guard for the shock absorber mounting (not shown in the illustration)
- the shock absorber from the trailing arm
- the screw for the torque rod mounting in the wheel bearing housing
- the anti-roll bar link from the anti-roll bar.
Caution! For certain versions, remove the lever for the level sensor from the left trailing arm.
Removing track rods and trailing arms (both sides)
Press the wheel bearing housing upwards so that the tie rod is horizontal.
Remove the cable for the parking brake from the mounting in the tie rod.
Remove:
- the screw for the tie rod in the wheel bearing housing. Unhook the tie rod from the wheel bearing housing. Lift up the tie rod further so that the screw in the trailing arm is exposed
- the screws for the trailing arm. First press the trailing arm outwards. Move it downwards at the inner mounting. Remove the trailing arm.
Removing the anti-roll bar
Remove the cables for the parking brake from their mountings in the lower cover and in the heat deflector plate.
Carefully bend out the mechanical cables towards the wheel bearing housing. Ensure that the cables do not crack or break.
Remove:
- the screws for the mountings for the anti-roll bar in the rear axle member
- the anti-roll bar.
Separate the connector for the Active on Demand coupling.
Removing the final drive from the rear axle member
Position mobile jack 998 5972 JACK 998 5972 Jack together with fixture 999 5972 FIXTURE 999 5972 Fixture.
Adjust the plate against the lower cover and final drive.
Install a large hose clamp or several clamps put together over the coupling (AOC (Active on Demand Coupling) / final drive and the plate.
Remove:
- the front screw for the final drive
- the 8 screws for the cover-rear axle member.
Lowering the final drive
First lower the final drive housing slightly and disconnect the air bleed hose from the nipple on top of the final drive.
Lower the final drive together with the drive shafts so that the center of the drive shaft is slightly below the center of the wheel bearing housings.
Pry out the wheel bearing housing. Remove the drive shaft from the hub.
Caution! Be very careful with the drive shaft when removing it from the hub. The inner joint may be damaged if the shaft releases under its own weight.
Replacing the final drive housing
When replacing the final drive, see Final drive, transferring components Final Drive, Transferring Components.
Replacing the drive shaft/drive shaft seal
When replacing the drive shafts and drive shaft seals, see Half shaft seal rear final drive housing, replacing, B5254T2, M58, B5254T2, AW50/51 AWD Half Shaft Seal Rear Final Drive Housing, Replacing.
Installation
Note! For tightening torques, see the relevant specifications.
Note! To ensure that there is no exhaust leakage, see Flanged joint, assembling Flanged Joint, Assembling.
Preparations for the installation of the final drive
Lift the final drive together with the drive shafts so that the center of the drive shaft is slightly below the center of the wheel bearing housings.
Apply rust-proofing agent to the ends of the drive shafts.
Press out one of the wheel bearing housings. Align the drive shaft in the hub.
Then align the other side.
Lift a little more and connect the bleed hose to the nipple on the final drive housing. Check that the hose is secured to the rear axle member by the tie strap and that it is not kinked.
Installing the final drive
Press the final drive up against the rear axle member. Align all screws.
Lightly tighten the screws alternately.
Tighten the 8 screws for the cover. See the relevant specifications.
Tighten the M12 screw for the front bushing in the final drive housing.
Remove the jack.
Connect the connector to the wiring harness for the Active on Demand coupling.
Installing the anti-roll bar on the rear axle member (both sides)
Install new lock nuts, M12. Tighten.
Note! Ensure that the cable for the parking brake passes above the ends of the anti-roll bar. Press the cables into place in the mountings on the heat deflector plate.
Installing trailing arms and track rods (both sides)
Raise the wheel bearing housing so that the hole for the trailing arm in the bearing housing and rear axle member is horizontal.
Install the trailing arm. Use new screws, M12. Tighten.
Install the tie rod on the wheel bearing housing. Use new lock nuts, M12. Tighten. Install the parking brake cable in the holder on the tie rod and in the cable mountings in the lower cover. Tighten. See Tightening torque [1][2]Specifications.
Installing shock absorbers, torque rods and anti-roll bar links (both sides)
Press the trailing arm downwards when the shock absorber is being installed. Use a crow bar.
Install:
- the shock absorbers on the trailing arms. Do not tighten the screw
- the screw for the tie rod/wheel bearing housing. Do not tighten the screw
- the link to the anti-roll bar on both sides. Use a new M12 nut. Tighten.
Caution! For certain versions, install the lever for the level sensor on the left trailing arm.
Installing the propeller shaft
Install the propeller shaft using the marking made earlier. See Removing the propeller shaft.
Check carefully that the mating surfaces on the propeller shaft and flange are clean.
Use new screws when installing the propeller shaft. First tighten the screws that are opposite each other. See the relevant specifications. Then tighten all screws crosswise. See the relevant specifications. Use counterhold 999 5743 Counterhold 999 5743 Counterhold.
Install:
- the support for the center bearing on the car body. Tighten
- the screws for the center bearing on the propeller shaft. Tighten.
Filling and checking the oil in the final drive
Fill the final drive with oil. Check the oil level. P/N 116 1620-8 (1 liter container)
Tighten the level plug. See the relevant specifications.
Volume approximately 0.7 l.
Filling and checking the oil in the Active on Demand Coupling
Fill and check oil in the clutch (AOC). Part number 116 1641 (0.3 liter container)
Tighten the level plug. See the relevant specifications.
Volume approximately 0.8 l.
Installing the rear section of the exhaust system
Note! Check that the gasket on the flange joint for the exhaust system is intact.
Install:
- the mountings for the exhaust system in the rear axle member
- the exhaust system to the front exhaust pipe/three-way catalytic converter (TWC) and the mountings in the rear axle member and the body.
Installing the rear wheels. Tightening shock absorbers and torque rods
Install:
- the M10 screws for the drive shafts on both sides. Use new screws. Tighten
- the rear wheels. See Installing wheels Service and Repair.
Position the car on a wheel track hoist.
Tighten the M12 screws for the shock absorbers and torque rods on both sides.
Install the protective covers over the shock absorber mounting.
Note! Check and adjust the rear wheel alignment if necessary. See the relevant specifications.