Remove/install complete rear axle

AR35.10-P-0010RT

Remove/install complete rear axle

18.02.2020

Model

251

Shown on model 251.1 with panoramic glass sunroof with top sliding sunroof code 413

2

Diagonal struts

6

Clip

3

Rear muffler

7a

Rear bolts

4

Lifting device

7b

Front bolts

5

Rear axle

8

Protective panels

Shown on model 251.1 with panoramic glass sunroof with top sliding sunroof code 413

9

Brake hose

15

Air spring

10

Strut rod

16

Connector

11

Brake pad thickness contact sensor connector coupling

17

Connector couplings

12

Connector

18

Locking lugs

13

Guide pin

19

Camber strut

14

Brake caliper

Shown on model 251.1 with panoramic glass sunroof with top sliding sunroof code 413

20

Left cable coupling

23

Threaded connection

21

Right cable coupling

24

Bolts

22

Level sensor plugs

25

Propeller shaft

 

Remove/install

 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

Topical note

Notes on installing brake hoses

AH42.10-P-9406-01A

Topical note

Notes on self-locking nuts and bolts

AH00.00-N-0001-01A

Notes on AIRmatic

AH32.22-P-1000-02RT

1

While working on the rear axle care must be taken to ensure that the surface of all aluminum components do not get any scratches, cracks and notches. Otherwise the service life of the parts will be affected

2

Raise the vehicle on a two-post vehicle lift until the wheels no longer touch the ground

AR00.60-P-1000RT

 Position support plates of 2-post vehicle lift so that the parts of the underbody paneling underneath can be loosened or removed.

3

Remove rear wheels



AP40.10-P-4050RT

4

Deflate rear air springs (15) with STAR DIAGNOSIS



AD00.00-P-2000-04A


The vehicle must not be standing on its wheels.
Otherwise the air springs (15) can be destroyed.

 Only for vehicles with air suspension on rear axle.

5

Switch off ignition and remove the transmitter key from the EIS [EZS] control unit

 On vehicles with code 889 Keyless-Go: Press Keyless-Go start/stop button repeatedly until the ignition is switched off. Remove transmitter key from vehicle and store it at a location beyond its transmission range (at least 2 m).

6

Remove left and right rear springs

 Only for vehicles with steel suspension on rear axle.

7

Open retaining clamps at brake hose (9) with suitable tool and unclip brake hose (9)

 On both sides of the vehicle.

8

Release and disconnect plug (16) at camber strut (19)

 On both sides of the vehicle.

 The number of plugs (16) may vary depending on vehicle equipment.

9

Unlock locking lugs (18) of connector couplings (17) in camber strut (19) (arrow) and detach connector couplings (17)


Do not use force.
Because the plug couplings (17) can easily tear off.

 Unlock connector couplings (17) using thin screwdriver or drift (arrow).

 On both sides of the vehicle.

 The number of connector couplings (17) may vary depending on the vehicle equipment.

 The plastic bar clipped into the camber strut (19) is not detached from the camber strut (19).

 Remove any existing cable ties.

10

Unlock plug (12) and detach from brake pad thickness contact sensor connector coupling (11)

 The brake pad thickness contact sensor is only present on one side of the vehicle.

11

Remove screw of brake pad thickness contact sensor connector coupling (11) and detach connector coupling from brake caliper (14)

AR42.10-P-0160RT

 Installation: Replace bolt.

12

Detach clamp from brake caliper (14) and remove plastic caps of guide pins (13)

 On both sides of the vehicle.

 Detach clamp using suitable tool.

13

Unscrew guide pins (13), remove brake caliper (14) and detach brake pads from brake caliper (14)

 On both sides of the vehicle.

 Installation: Check brake pads, brake caliper (14), guide pins (13), brake pad thickness contact sensor, pistons and dust boots, replace if necessary.
Clean contact surfaces of brake pads on brake caliper (14).
Do not use sharp-edged or pointed objects to clean contact surface. Install brake pads without lubrication.

Press back piston using pusher tool:



Remove/install brakepads on floating brake caliper

AR42.10-P-0160RT

 Resetting device

*000589524300

14

Pass brake caliper (14) between strut rod (10) and air spring (15) and fasten to shock absorber


Do not kink or twist the brake hose (9),
otherwise, it may be damaged.


Clamp a rag or other similar soft shim between brake caliper (14) and shock absorber,
otherwise, the paint of the shock absorber can be damaged.

 On both sides of the vehicle.

15

Attach left and right guard plates (8)

 Guard plate

*220589013100

16

Raise vehicle on two-post lift

17

Fasten vehicle securely to 2-post vehicle lift

 Vehicle hoist securing tool

*169589023100

18

Remove diagonal struts (2)

AR61.10-P-5138RT

 For vehicles with panoramic glass sunroof with top sliding sunroof code 413.

19

Remove left and right rear mufflers (3)

Engine 113, 156

AR49.10-P-4951RT

Engine 272, 273

AR49.10-P-7100GZA

Engine 642

AR49.10-P-7100GZB

20

Unhook hand brake cable at rear of rear axle carrier from right cable coupling (21), then from left cable coupling (20)

21

Unclip hand brake cable from retaining clip (6)

22

Release and disconnect level sensor plugs (22) on left and right sides of vehicle

23

Mark position of propeller shaft (25) relative to vibration damper and to flange of rear axle differential

 Installation: Align propeller shaft (25) and flange of differential with markings.

24

Remove screws (24) and slide propeller shaft (25) forward as far as possible

 Self-locking bolt, flexible coupling to rear axle differential

*BA41.10-P-1002-01G

 Retainer wrench

*164589020700

25

Remove threaded connection (23) at bottom of left shock absorber and at bottom of right shock absorber

 Self-locking nut, shock absorber to spring control arm

*BA32.25-P-1001-03L

26

Securely support rear axle (5) with suitable lifting device (4), e.g. axle jack, and additionally secure rear axle (5) on lifting device (4)

27

Remove front screws (7b) and rear screws (7a)

 Self-locking bolt, rear axle carrier at front and rear to frame floor

*BA35.10-P-1001-01L

28

Slowly lower the rear axle (5) diagonally towards the rear, guiding the journal on the flange of the rear axle differential out of the propeller shaft (25)


Ensure that the journal on the flange of the rear axle differential
is not damaged when lowering the rear axle (5).

 Installation: Guide the journal on the flange of the rear axle differential into the propeller shaft (25) while lifting the rear axle (5).

29

Check rear axle (5) for damage, replace damaged parts

30

Install in the reverse order



Check

31

Check oil level in rear axle differential, correct if necessary

 Oil filler screw, differential

*BA35.31-P-1001-02F

Loctite 7063 (400 ml) cleaning spray

*BR00.45-Z-1046-04A

Sealant, Omnifit 100H (50 g)

*BR00.45-Z-1061-01A

32

Perform wheel alignment check

AR40.20-P-0200RT

33

Adjust the zero position of the xenon headlamps



AD00.00-P-2000-04A

 Only on vehicles with bi-xenon headlamp unit with integrated curve illumination, code 615, and only if suspension components were replaced or if the vehicle level was adjusted.

34

Check headlamp adjustment, correct if necessary



AP82.10-P-8260RT

 Only if suspension components were replaced or if the vehicle level was adjusted.

 Rear axle shock absorber

Number

Designation

Model 251

BA32.25-P-1001-03L

Self-locking nut, shock absorber to spring control arm

Stage 1

Nm

100

Stage 2

°

120

 Rear axle carrier

Number

Designation

Model 251

BA35.10-P-1001-01L

Self-locking bolt, rear axle carrier at front and rear to frame floor

Stage 1

Nm

100

Stage 2

°

–180

Stage 3

Nm

100

Stage 4

°

90

 Rear axle differential housing

Number

Designation

Model 251

BA35.31-P-1001-02F

Oil filler screw, differential

Nm

35

 Propeller shaft

Number

Designation

Model 251

BA41.10-P-1002-01G

Self-locking bolt, flexible coupling to rear axle differential

Nm

64

Repair materials

Number

Designation

Order number

BR00.45-Z-1046-04A

Loctite 7063 (400 ml) cleaning spray

A 001 986 71 71 09

BR00.45-Z-1061-01A

Sealant, Omnifit 100H (50 g)

A 002 989 23 71