31 11 506 Lowering/raising front axle carrier
Special tools required:
- 00 2 030 . See MAINTENANCE AND GENERAL INFORMATION - SPECIAL TOOLS .
- 00 2 040
- 31 4 012 . See FRONT AXLE - SPECIAL TOOLS .
- 33 3 274 . See REAR AXLE - SPECIAL TOOLS .
Secure engine in installation position to prevent it from falling down. See 11 00 670 SECURING ENGINE IN INSTALLATION POSITION (N52, N53) .
DANGER OF POISONING IF OIL IS INGESTED/ABSORBED THROUGH THE SKIN !
RISK OF INJURY IF OIL COMES INTO CONTACT WITH EYES AND SKIN !
Seal off hydraulic lines with plugs.
Necessary preliminary tasks:
- Secure engine in installation position . See 11 00 670 SECURING ENGINE IN INSTALLATION POSITION (N52, N53) .
- Remove reinforcement plate
- If necessary, remove steering gear cover on both sides
- If necessary, remove wheel suspension cover on both sides
- Remove lower steering spindle from power steering gear. See 32 31 070 REMOVING AND INSTALLING / REPLACING LOWER SECTION OF STEERING SPINDLE .
- If necessary, disconnect plug connection on EH converter and expose line up to engine carrier
- If necessary, disconnect plug connection on ride-height sensor and expose line up to engine carrier
- If necessary, unclip vacuum line for engine mount on engine support arm
Version with Dynamic Drive:
Draw off and dispose off hydraulic fluid from fluid reservoir.
Remove bottom right wheel arch trim . See 51 71... REMOVING AND INSTALLING/REPLACING FRONT (BOTTOM) RIGHT WHEEL ARCH TRIM .
Release nut (1) for Dynamic Drive return line.
Tightening torque 37 14 21AZ . See 14 ELECTRICAL COMPONENTS .
Release nut (2) for Dynamic Drive pressure line.
Tightening torque 37 14 13AZ . See 14 ELECTRICAL COMPONENTS .
Release nuts (3) for pressure lines to front axle oscillating motor.
Tightening torque 37 14 13AZ . See 14 ELECTRICAL COMPONENTS .
Version with active steering:
Disconnect plug connections (1, 2).
Expose wiring harness (3) up to front axle carrier.
Failure to comply with the following instructions may result in the vehicle slipping off the lifting platform and critically injuring other persons.
When supporting components, make sure that
- the vehicle can no longer be raised or lowered
- the vehicle does not lift off the locating plates on the lifting platform
If necessary, position special tool 00 2 040 with a 2nd person helping on workshop jack 00 2 030 .
Insert special tool 314012 into corresponding receptacles of special tool 00 2 040 .
Align special tool 00 2 040 to front axle carrier.
Support front axle carrier in rear area by raising special tool 00 2 040 .
Position special tool 33 3 274 on floor jack mounting.
When lowering and raising, make sure the cover for the relevant tension strut rubber mount is free to move.
Release screws (1, 2).
Installation:
Check threads for damage; if necessary, repair with Helicoil thread inserts.
Tighten down screws (1) and then screws (2).
Tightening torque 31 10 1AZ . See 10 FRONT AXLE SUSPENSION .
The following operation must be carried out during lowering:
- N54 with automatic transmission: Release screws (1) and remove bracket (2) for transmission oil cooler lines from front axle carrier
Lower front axle carrier 100 mm.
After installation:
- Version with Dynamic Drive:
- Fill and bleed hydraulic system . See 32 13 006 BLEEDING POWER STEERING (VERSION WITH DYNAMIC DRIVE) .
- Check pipe connections for leaks
- Carry out steering angle sensor adjustment/adjustment for active steering . See 32 10 005 ADJUSTMENT FOR ACTIVE FRONT STEERING or 61 31 996 CARRYING OUT STEERING ANGLE SENSOR ADJUSTMENT .
- Carry out initial Dynamic Drive operation . See 37 10 001 INITIAL OPERATION WITH TEST RUN OF DYNAMIC DRIVE .