31 31 Adjusting front spring strut
Special tools required:
- 31 3 340
- 31 3 341
- 2 318 833
- 2 356 943
Before adjusting the spring strut, the actual value of the VEHICLE HEIGHT must be measured.
Spring struts must only be adjusted with pretensioned coil springs. Noncompliance can cause damage to the thread of the height adjustment on the spring strut.
All the safety precautions and instructions contained in the Owner's Handbook must be strictly observed!
Failure to observe these safety precautions and instructions increases the risk of serious physical injury, damage to your health and damage to property and equipment!
- Prior to each use, check the special tools for defects, modifications and operational reliability.
- Damaged/modified special tools must not be used!
- No changes or modifications may be made to the special tools!
- These special tools are intended solely for the purpose of tightening and relieving cylindrical and tapered suspension springs.
- Keep special tools dry, clean and (down to the spindle) free from grease.
- Impact screwdrivers are prohibited!
- Do not compress coil spring to full extent.
Necessary preliminary work:
- Remove FRONT SPRING STRUT SHOCK ABSORBER .
Clamp special tool 31 3 341 in vice.
Fit special tools 2 318 833 from above on special tool 31 3 341 until locking pins (1) can be felt and heard to snap into place.
Clean coil spring to remove contamination.
Spring must be free of grease, clean and dry.
Accommodate coil spring with special tools 2 318 833.
Tension coil spring until the lower spring cup is relieved.
Use the table below to calculate how many times the adjusting nut needs to be turned in order to compensate for the height offset:
- If the vehicle is too high, the adjusting nut must be adjusted downwards.
- If the vehicle is too low, the adjusting nut must be adjusted upwards.
| Vehicle height adjustment required (in mm) | Turns of the adjusting nut |
|---|---|
| 0.8 | 1 |
| 1.1 | 1.5 |
| 1.5 | 2 |
| 1.9 | 2.5 |
| 2.3 | 3 |
| 2.6 | 3.5 |
| 3 | 4 |
| 3.4 | 4.5 |
| 3.8 | 5 |
| 4.1 | 5.5 |
| 4.5 | 6 |
| 4.9 | 6.5 |
| 5.3 | 7 |
Make a mark on the adjusting nut.
- (This mark can be used to count the turns of the adjusting nut.)
Undo bottom nut using special tool 2 356 943 C and a torque wrench.
- Counterhold top nut using special tool 2 356 943 A.
Adjust adjusting nut (bottom nut) by the calculated number of turns.
Bring lock nut (top nut) into contact with spring cup.
Tighten adjusting nut (bottom nut) using special tool 2 356 943 C and a torque wrench.
- Counterhold top nut using special tool 2 356 943 A.
Tightening torque 31 31 4AZ .
Check position of spring pad pin (1).
Pin (1) must be in bore hole of spring cup.
Bottom coil spring end must be at limit position (2) of spring pad.
Check top spring pad is positioned correctly.
Upper coil spring end must be at limit position of spring pad.
Relieve tension on coil spring.
Remove spring strut from spring tensioner.
- Install FRONT SPRING STRUT SHOCK ABSORBER .
- Check VEHICLE RIDE HEIGHT .