Rear Axle

WM 390119 Removing and installing rear final drive








Preliminary work for rear final drive

1. Remove exhaust system.
2. Remove longitudinal interlock servo motor.

Removing rear final drive





Overview of removing and installing rear final drive

1. Move selector lever to position N.
2. Loosen fastening screws for fixing cardan shaft center bearing holder to body.





Cardan shaft holder to body

3. Loosen bolts for fixing center bearing to holder.





Center bearing to cardan shaft holder

Information:
- The color marking, match point, on the cardan shaft and on the flange of the rear final drive must be installed in alignment -arrows-. This will neutralize the residual imbalance of the components.





Match points on the cardan shaft

Information:
- To loosen the cardan shaft on the rear axle transmission, a second fitter should counter the fastening screws on the triangular flange of the transfer box.

4. Remove cardan shaft from rear axle differential and tie it up.





Tying up rear cardan shaft

Information:
- To loosen the drive shaft bolts on the rear axle transmission, a second fitter should sit in the vehicle and block the rear-axle final drive by actuating the foot brake.

5. Remove both drive shafts on transmission side and tie them up.





Removing rear drive shaft

6. Support transmission jack and rear axle differential with a retaining strap.
7. Unscrew fastening screws for final drive. To do this, counter with a ring wrench.





Mount for rear final drive

8. Tip drive flange upwards and gradually drain rear axle differential. Remove vent line at the same time.





Removing rear final drive

9. Remove transmission and pull off vent line.





Removing vent line

Removing rear final drive (with PDCC)





Overview of rear final drive

1. Move selector lever to position N.
2. Loosen fastening screws for fixing cardan shaft center bearing holder to body.





Cardan shaft holder to body

3. Loosen bolts for fixing center bearing to holder.





Center bearing to cardan shaft holder

Information:
- The color marking, match point, on the cardan shaft and on the flange of the rear final drive must be installed in alignment -arrows-. This will neutralize the residual imbalance of the components.





Match points on the cardan shaft

Information:
- To loosen the cardan shaft on the rear axle transmission, a second fitter should counter the fastening screws on the triangular flange of the transfer box.

4. Remove cardan shaft from rear axle differential and tie it up.





Tying up rear cardan shaft

Information:
- To loosen the drive shaft bolts on the rear axle transmission, a second fitter should sit in the vehicle and block the rear-axle final drive by actuating the foot brake.

5. Remove both drive shafts on transmission side and tie them up.





Removing rear drive shaft

Caution:
Kinked or overstretched lines
- Leaks in the hydraulic system

- Only lower anti-roll bar slightly and secure it to the chassis.

6. Unscrew fastening screws on anti-roll bar and lower the anti-roll bar until you have easy access to the two screws on the rear final drive.





Securing anti-roll bar

7. Use tie-wraps, for example, to fix the anti-roll bar in place at this position on the axle mount.





Fixing anti-roll bar in place

8. Support transmission jack and rear axle differential with a retaining strap.
9. Unscrew fastening screws for final drive. To do this, counter with a ring wrench.





Mount for rear final drive

10. Tip drive flange upwards and gradually drain rear axle differential. Remove vent line at the same time.





Removing rear final drive

11. Remove transmission and pull off vent line.





Removing vent line

Installing rear final drive

Information:
- Screws which are tightened with a torque angle must be replaced with new ones.





Mount for rear final drive

Information:
- The color marking, match point, on the cardan shaft and on the flange of the rear final drive must be installed in alignment -arrows-. This will neutralize the residual imbalance of the components.





Match points on the cardan shaft

1. Secure rear axle transmission on transmission jack with retainer band.
2. Run in rear axle differential by gradually tipping the drive flange upwards . Connect bleeder line at the same time.





Installing transmission

3. Screw in new fastening screws on final drive. To do this, counter with ring wrench. - Initial tightening: 90 Nm (67 ftlb.) - Final tightening: 90°

Information:
- To tighten the drive shaft bolts on the rear final drive, a second fitter should sit in the vehicle and block the rear-wheel drive assembly by actuating the foot brake.

4. Attach drive shafts with new screws.

Caution:
Cardan shaft can be damaged by imbalance.

- Cardan shaft and flange not installed in original position.

- The color marking, match point, on the cardan shaft and on the flange of the rear final drive must be installed in alignment. This will neutralize the residual imbalance of the components.

Information:
- To attach the cardan shaft to the rear final drive, a second fitter should counter the fastening screws on the triangular flange of the transfer box.

5. Attach cardan shaft with new screws.





Cardan shaft to rear final drive

6. New fastening screws must be used to secure the cardan shaft center bearing holder to the body. - Tightening torque: 60 Nm (44 ftlb.)





Cardan shaft holder to body

Information:
- Center bearing must be installed without tension.
- Fit special centering tool 9680 in the order specified.





Installation position for special tool

7. Position special centering tool 9680.





Alignment of special tool 9680

8. Press on special centering tool 9680 in sequence according to numbering -1, 2-.





Installation of special tool 9680

9. Tighten threaded joints connecting holder to center bearing. - Tightening torque: 20 Nm (15 ftlb.)





Cardan shaft holder to center bearing

10. Remove special centering tool 9680.





Removal of special tool 9680

Installing rear final drive (with PDCC)

Caution:
Kinked or overstretched lines
- Leaks in the hydraulic system

- Only lower anti-roll bar slightly and secure it to the chassis.

Information:
- Screws which are tightened with a torque angle must be replaced with new ones.





Mount for rear final drive

Information:
- The color marking, match point, on the cardan shaft and on the flange of the rear final drive must be installed in alignment -arrows-. This will neutralize the residual imbalance of the components.





Match points on the cardan shaft

Caution:
Kinked or overstretched lines
- Leaks in the hydraulic system

- Only lower anti-roll bar slightly and secure it to the chassis.

1. Unscrew fastening screws on anti-roll bar and lower the anti-roll bar until you have easy access to the two screws on the rear final drive.





Securing anti-roll bar

2. Use tie-wraps, for example, to fix the anti-roll bar in place at this position on the axle mount.





Fitting anti-roll bar in place

3. Secure rear axle differential on transmission jack with a retainer strap.
4. Run in rear axle differential by gradually tipping the drive flange upwards . Connect vent line at the same time.





Installing transmission

5. Screw in new fastening screws on final drive. Always counter with a ring wrench. - Initial tightening: 90 Nm (67 ftlb.) - Final tightening: 90°
6. Screw in fastening screws on anti-roll bar. - Tightening torque: 60 Nm (44 ftlb.)





Securing anti-roll bar

Information:
- To tighten the drive shaft bolts on the rear final drive, a second fitter should sit in the vehicle and block the rear-wheel drive assembly by actuating the foot brake.

7. Attach drive shafts with new screws.

Caution:
Cardan shaft can be damaged by imbalance.

- Cardan shaft and flange not installed in original position.

- The color marking, match point, on the cardan shaft and on the flange of the rear final drive must be installed in alignment. This will neutralize the residual imbalance of the components.

Information:
- To attach the cardan shaft to the rear final drive, a second fitter should counter the fastening screws on the triangular flange of the transfer box.

8. Attach cardan shaft with new screws.





Cardan shaft to rear final drive

9. New fastening screws must be used to secure the cardan shaft center bearing holder to the body. - Tightening torque: 60 Nm (44 ftlb.)





Cardan shaft holder to body

Information:
- Center bearing must be installed without tension.
- Fit special centering tool 9680 in the order specified.





Installation position for special tool

10. Mount special centering tool 9680.





Alignment of special tool 9680

11. Press on special centering tool 9680 in sequence according to numbering -1, 2-.





Installation of special tool 9680

12. Tighten screws securing holder to center bearing. - Tightening torque: 20 Nm (15 ftlb.)





Cardan shaft holder to center bearing

13. Remove special centering tool 9680.





Removal of special tool 9680

Subsequent work for rear final drive

1. Install the exhaust system.
2. Install servo motor for rear-differential lock.