Front Suspension

Air Suspension Strut, Mounting Bracket and Upper Control Arm Assembly Overview






1 Mounting Bracket

• Suspension strut with mounting bracket, removing and installing, refer to => [ Air Suspension Strut with Mounting Bracket ] Air Suspension Strut with Mounting Bracket.

• Tightening specification for attaching the upper control arm to the bracket => [ (Item 5) Bolt ] Removal and Replacement and => [ (Item 25) Bolt ] Removal and Replacement.

2 Bolt

• 50 Nm + 90° turn

• Always replace if removed.

• Follow tightening sequence. Refer to => [ Tightening specification of threaded connection depicted as numbered is mandatory. ] Air Suspension Strut with Mounting Bracket.

3 Nut

• 23 Nm

4 Nut

5 Wheel Bearing Housing

6 Bolt

• 45 Nm

7 Residual Pressure Retaining Valve

• Do not loosen.

8 Connector Piece

• 3 Nm

• Always observe tightening specification!

• Only remove if vehicle is raised and air spring damper is unloaded (otherwise, there is a risk of injury from lowering vehicle).

• Service the air line if there are leaks. Refer to => [ Air Pipe Line, Servicing ] Description and Operation.

• Or, replace the connection. Refer to => [ Connector Piece, Replacing ] Connector Piece, Replacing.

• Clean connections before loosening.

• Air escapes when connections are unscrewed.

9 Air Line

• Colors: front left - red; front right - green.

• Air pipe line, servicing, refer to => [ Air Pipe Line, Servicing ] Description and Operation.

• Replace connector piece if leaking, refer to => [ Connector Piece, Replacing ] Connector Piece, Replacing.

10 Left Front Dampening Adjustment Valve (N336) or Right Front Dampening Adjustment Valve (N337)

• Removing and installing, refer to => [ Dampening Adjustment Valve ] Dampening Adjustment Valve.

11 Nut

• Always replace if removed.

12 Track Control Arm

13 Bolt

• 90 Nm + 90° turn

• Always replace if removed.

14 Nut

• 8 Nm

15 Left Front Level Control System Sensor (G78) or Right Front Level Control Sensor (G289)

• Only remove and install or replace completely. Refer to => [ Front Level Control System Sensor ] Front Level Control System Sensor.

• The sensor lever must point forward.

• After loosening, check basic setting of headlamp adjustment.

• After loosening, control position must be adapted anew in vehicles with air spring suspension. Refer to => [ Self-Leveling Suspension Control Position, Programming ] Self-Leveling Suspension Control Position, Programming.

Calibrate the lane assist after loosening. Refer to => [ Lane Assist Calibration Procedure ] Lane Assist Calibration Procedure.

16 Clamp

• Is installed only during a repair.

17 Boot

• Replacing, refer to => [ Boot ] Boot.

18 Clamp

19 Air Spring Shock Absorber

• Removing and installing, refer to => [ Air Suspension Strut with Mounting Bracket ] Air Suspension Strut with Mounting Bracket.

• Replacing dampening adjustment valve, refer to => [ Dampening Adjustment Valve ] Dampening Adjustment Valve.