Remove/install the suspension strut

AR32.25-S-1017E

Remove/install the suspension strut

27.07.2020

Model

447, 448

Modification notes

06.07.2020

Method revised.

The whole document

Shown on model 447.8 on right side of vehicle

1

Brake hose

2a

Electric line

2b

Electric line

3

Suspension strut

4

Bolts

5

Bolts

Shown on model 447 with code CA4 (AIRMATIC), right side of vehicle

1

Brake hose

2a

Electric line

2b

Electric line

3

Suspension strut

4

Bolts

5

Bolts

6

Pressure line

7

Mounting clip

 Danger

Risk of death caused by vehicle slipping or toppling off of the lifting platform.

Align vehicle between vehicle lift columns and position the four support plates at the vehicle lift support points specified by the vehicle manufacturer.

AS00.00-Z-0010-01A

 Warning

Risk of injury caused by pinching or crushing when working on springs or spring bodies that are under tension

Use only approved tensioning devices; additionally screen off hazardous area if necessary. Check special tools for damage and proper operation (visual inspection). Wear protective gloves.

AS00.00-Z-0001-01A

 Warning

Risk of injury. Skin or eye injuries may result when handling hot or glowing objects.

Wear protective gloves, protective clothing and safety glasses, if necessary.

AS00.00-Z-0002-01A

 Caution

Risk of injury caused by scraping or cutting body parts on sharp vehicle parts

Always wear protective gloves when working on or near sharp and non-deburred vehicle parts.
Deburr repair panels.

AS00.00-Z-0017-01A

Topical note

Notes on threaded connections fastened using a tightening angle-based tightening process

AH00.00-P-0020-01A

Topical note

Notes on air suspension

Model 447
with code CA4 (AIRMATIC)

AH32.22-N-1000-01E

Note on calculation of tightening torque when using insertion or socket tools with various effective lengths

AH00.00-P-0015-01CW

Notes on repair work on suspension components

AH00.00-P-0100-01A



Remove

1

Remove air/water duct.

AR83.25-S-1410E

2

Raise vehicle.

AR00.60-S-1000E

 Raise until all wheels are clear of the ground.

3

Empty air suspension.

Model 447
with code CA4 (AIRMATIC)

AR32.22-S-2019E

4

Remove each front wheel.

AR40.10-S-1100E

5

Remove brake hose (1) from suspension strut (3).

7

Remove electric line (2b) for brake pad wear sensor from suspension strut (3).

When removing the right suspension strut(3).

8

Remove pressure line (6) from suspension strut (3).

Model 447
with code CA4 (AIRMATIC)

 To do so, first remove pressure line (6) from retaining clip (7) and then from suspension strut (3).
Use suitable open end wrench bit in combination with  socket wrench socket.
Seal connections.

 Record plug

*129589009100

 Socket wrench bit

*211589000900

9

Remove torsion bar linkage from suspension strut (3).

AR32.35-S-3328E

10

Remove screws/bolts (4).

 To do so, counterhold nuts of screws (4).

11

Remove suspension strut (3).

 To do this, remove the bolts (5).
Aid of helper required.

12

Disassemble suspension strut (3).

When replacing suspension components.

Model 447
except code CA4 (AIRMATIC)
Model 448

AR32.25-S-1018E



Install

13

Assemble suspension strut (3).

When replacing suspension components.

Model 447
except code CA4 (AIRMATIC)
Model 448

AR32.25-S-1018E

14

Position suspension strut (3) and turn in screws (5).

 Replace bolts (5).

 Bolt, suspension strut to body

*BA32.25-N-1004-04C

15

Turn in screws (4) and tighten nuts of screws (4).

 Replace bolts (4) and nuts.
Tighten nuts of screws (4) to 1st torque stage.
Only tighten nuts of screws (4) during wheel alignment measurement to 2nd torque stage and to tightening angle of 3rd torque stage.

 Collar bolt, suspension strut to steering knuckle

*BA32.25-N-1001-04C

 Cam bolt, suspension strut to steering knuckle

*BA32.25-N-1002-04C

16

Attach torsion bar linkage to suspension strut (3).

AR32.35-S-3328E

17

Attach pressure line (6) to suspension strut (3).

Model 447
with code CA4 (AIRMATIC)

 To do so, remove stop plugs.
Use suitable open end wrench bit in combination with  socket wrench socket.

 Retaining screw, pressure line to front suspension strut

*BA32.22-N-1005-03EA

 Record plug

*129589009100

 Socket wrench bit

*211589000900

18

Attach electric line (2b) for brake pad wear sensor to suspension strut (3).

When installing the right suspension strut(3).

 Check electric line (2b) for brake pad wear sensor for damage.

If damage is present,



replace electric line (2b) for brake pad wear sensor.

AR54.18-S-7433E

19

Attach electric line (2a) of rotational speed sensor to suspension strut (3).

 Check electric line (2a) of rotational speed sensor for damage.

If damage is present,



Replace rpm sensor.

AR42.30-S-0712E

20

Attach brake hose (1) to suspension strut (3).

 Check brake hose(1) for damage.

If damage is present,



Replace brake hose (1).

AR42.10-S-0024E

21

Mount front wheel.

AR40.10-S-1100E

 Model 447
with code CA4 (AIRMATIC)
The wheels must not yet make contact with the ground.

22

Fill air suspension.

Model 447
with code CA4 (AIRMATIC)

AR32.22-S-2019E

23

Install air/water duct.

AR83.25-S-1410E

24

Perform chassis alignment.

AR40.20-S-0200E

 Component parts of air suspension

Number

Designation

Model 447
with code CA4 (AIRMATIC)

BA32.22-N-1005-03EA

Retaining screw, pressure line to front suspension strut

Nm

2

 Suspension struts

Number

Designation

Model 447, 448

BA32.25-N-1001-04C

Collar bolt, suspension strut to steering knuckle

Stage 1

Nm

150

Loosen

°

180

Stage 2

Nm

120

Stage 3

°

75

 Suspension struts

Number

Designation

Model 447, 448

BA32.25-N-1002-04C

Cam bolt, suspension strut to steering knuckle

Stage 1

Nm

150

Loosen

°

180

Stage 2

Nm

120

Stage 3

°

75

 Suspension struts

Number

Designation

Model 447, 448

BA32.25-N-1004-04C

Bolt, suspension strut to body

Stage 1

Nm

40

Stage 2

°

90