Remove/install front axle

AR33.10-P-0100FR

Remove/install front axle

16.01.2020

Model

257

Shown except code M005 (4MMATIC), with radiator package (1) in rear installation position

1

Cooler package

5

Condenser

2

Tensioning strap

6

Radiator seat

3

Refrigerant line

7

Aluminum strut

4

Front axle

8

Air duct segments

Shown except CODE M005 (4MATIC)

4

Front axle

9

Electrical connector

10

Electrical connector

11

Rack-and-pinion steering

12

Wiring harness for rack-and-pinion steering

Shown with code M005 (4MMATIC), with radiator package in front installation position

7

Aluminum strut

14

Screw

13

Radiator seat

15

Diagonal strut

Shown except code M005 (4MMATIC), with radiator package in rear installation position

4

Front axle

7

Aluminum strut

18

Bolts

19

Screw

20

Screw

21

Bolts

22

Elastomer bearing

Vehicles with code M005 (4M ATIC)

4

Front axle

18

Bolts

20

Screw

7

Aluminum strut

19

Screw

26

Bracket

M43/6

Low temperature circuit circulation pump 1

4

Front axle

24

Lifting platform

25

Tensioning strap

23

Tensioning strap

 Warning

Risk of poisoning caused by inhaling overheated refrigerant vapors from an air conditioning system containing R134a. Risk of injury to skin and eyes caused by contact with liquid R134a refrigerant and when working on pressurized parts

Never perform welding work on or near a closed air conditioning system. No smoking or open flames. Wear safety glasses and protective gloves. Work only in well ventilated rooms. Carry out repair work on the air conditioning system circuit only after the system has been evacuated.

AS83.00-Z-0006-01A

 Danger

Risk of fire due to ignition of R1234yf refrigerant on hot components. Risk of poisoning caused by inhaling overheated refrigerant vapors. Risk of injury to skin and eyes caused by contact with escaped R1234yf refrigerant and when working on pressurized parts. Risk of explosion due to formation of ignitable refrigerant/air mixtures

Never perform welding work on or near a closed air conditioning system. No smoking or open flames. Wear safety glasses and protective gloves. Work only in well ventilated rooms. Carry out repair work on the air conditioning system circuit only after the system has been evacuated.

AS83.00-Z-0007-01A

 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

Protect air conditioning circuit and components from moisture when carrying out repair work

AH83.30-N-0005-01A

Topical note

Notes on installation position of condenser

AH83.30-P-0002-01LW

Topical note

Notes on self-locking nuts and bolts

AH00.00-N-0001-01A

Notes on handling refrigerant R134a

AH83.30-N-0003-01A

Notes on handling refrigerant R1234yf

AH83.30-P-0003-02A

Notes on safety-relevant components

AH00.00-Z-0019-01A

Notes on repair work on suspension components

AH00.00-P-0100-01A

 

Remove/install

1

Raise vehicle and fix in place on vehicle lift.

AR00.60-P-1006A

2

Release pressure of air suspension using vehicle diagnosis system.

Model 257
with code 489 (AIR BODY CONTROL)



AD00.00-P-2000-06FR

3

Deactivate easy entry and exit feature using Audio/COMAND control panel.

Model 257
with code 275 (Memory Package (driver's seat, steering column and mirror))

4

Turn rack-and-pinion steering (11) to center position and fix steering wheel in place with holding device.

AR46.20-P-0500-01FR

 Retainer device

*129589012100

5

Discharge air conditioning system.

AR83.30-P-1760FR

6

Mount engine support fixture.

Model 257

Model 257 with engine 256.9

AR01.10-P-2400-18MSA

Model 257 with engine 656

AR01.10-P-2400-18OIB

 Adaptation plates

*240589003200

 Adapter kit

*240589013100

 Engine lifting device

*240589006100

 Engine hoist

*205589006100

7

Remove front wheels.

AR40.10-P-1102A

8

Remove engine compartment lining at front, center and rear.

AR61.20-P-1105FR

9

Secure radiator package (1) against falling down using tensioning strap (2).


Do not tighten tensioning strap (2) too far.
Otherwise the components can be damaged.

10

Remove refrigerant line (3) at condenser (5), hang to one side and seal connections.

 Installation: Install new seals.

 Nut/bolt, refrigerant line to condenser

*BA83.30-P-1006-01R

 Record plug

*129589009100

11

Unscrew screw (14), fold up left and right radiator mount (13) and remove from aluminum strut (7).

If the radiator package (1) is installed in the front installation position.

 Installation: Make sure that the radiator mounts (13) are seated correctly.

12

Remove front axle shafts and fix right and left steering knuckle in place on strut rod using tensioning strap (25).

Model 257 with engine 256 with transmission 725.0
with code M005 (Vehicles with 4MATIC/all-wheel drive)

AR33.30-P-0620MSA

Model 257 with engine 656 with transmission 725.0
with code M005 (Vehicles with 4MATIC/all-wheel drive)

AR33.30-P-0620OIB


The steering knuckles must NOT fold outward after they are detached from the upper transverse control arms.
Otherwise ball joints may be damaged.

13.1

Remove brake calipers with brakepads and attach to the vehicle with the brake hose attached and free of tension.

Model 2574-piston fixed-caliper brake

Model 257.3614-piston fixed-caliper brake

AR42.10-P-0070FRB

Model 257 (except 257.361)4-piston fixed-caliper brake

AR42.10-P-0070FRA

13.2

Remove brake caliper with brake caliper support and secure at vehicle with connected brake hose free of tension.

Model 2571-piston floating caliper brake

AR42.10-P-0070FR

14

Remove suspension struts from spring links.

Model 257
with code 489 (AIR BODY CONTROL)

AR32.25-P-1017FRA

Model 257
except code 489 (AIR BODY CONTROL)

AR32.25-P-1017FR

15

Unhook electrical wiring harnesses from holders on spring links and axle carrier and place to one side.

Model 257
with code M005 (Vehicles with 4MATIC/all-wheel drive)

16

Remove torsion bar linkages from spring link.

Model 257
except code M005 (Vehicles with 4MATIC/all-wheel drive)

AR32.35-P-3330FR

17

Remove left front axle rpm sensor line bracket and right front axle rpm sensor line bracket from front axle carrier and hang to the side with connected electric lines.

Model 257 (except 257.361)
except code M005 (Vehicles with 4MATIC/all-wheel drive)

AR42.30-P-0713FR

 Warning

Risk of injury. Moving parts can pinch, crush or, in extreme cases even sever extremities.

No parts of the body or limbs should be within the operating area of mechanical components when moving components.

AS00.00-Z-0009-01A

18

Disconnect steering coupling.

AR46.10-P-8000-01FR


Do not twist steering wheel when the steering coupling was removed.
Otherwise the clock spring contact will be destroyed.

 Engine mount wrench set

*001589011600

19

Disconnect electrical connectors (9, 10).

20

Remove rack-and-pinion steering wiring harness (12) completely from rack-and-pinion steering (11) and front axle (4) and place to one side.

21

Remove AIR BODY CONTROL compressor.

Model 257
with code 489 (AIR BODY CONTROL)

AR32.22-P-2001FR

22

Remove left and right diagonal strut (15).

 Mount, support (strut)

*BA33.10-P-1002-01Q

23.1

Remove screws (21) of front axle (4) from engine mounts.

Model 257
except code M005 (Vehicles with 4MATIC/all-wheel drive)

 Bolt, front engine mount to front axle carrier

*BA22.10-P-1002-03N

23.2

Remove screws of engine mounts from front axle (4).

Model 257
with code M005 (Vehicles with 4MATIC/all-wheel drive)

Model 257 with engine 256
with code M005 (Vehicles with 4MATIC/all-wheel drive)

AR22.10-P-4330MSA

Model 257 with engine 656
with code M005 (Vehicles with 4MATIC/all-wheel drive)

AR22.10-P-4330OIB

24

Remove holder (26) with low-temperature circuit circulation pump 1 (M43/6) from crossmember and hang to one side with connected lines.

25

Lift engine far enough using engine support fixture so that guide pins of engine mounts are fully extended out of the front axle (4).

26

Position lifting platform (24) on front axle (4) and secure with tensioning strap (23).



000 588 03 62 00 Lifting platform

WS01.00-P-0091A

27

Remove holders of engine compartment lining from aluminum struts (7).

28

Unscrew screws (19).

29

Remove screws (20) of front axle (4).

Topical note

Notes on bolted connections with self tapping screws

AH00.00-P-0007-01SF

 Bolt, front axle carrier to longitudinal member

*BA33.10-P-1001-01Q

30

Release air duct segments (8) and fold inward.

 Installation: Note positioning of outside temperature sensor.

31

Lower front axle (4) slightly.


Observe radiator package (1) when lowering.
Otherwise it may be damaged.

32

Push spring links downward and position suspension struts in front of spring links.


Carefully position the suspension struts in front of the spring control arms.
Otherwise the suspension strut joints can be damaged.

33

Mark aluminum struts (7) relative to front axle (4) using colored pencil.

34.1

Remove screws (18).

If the radiator package (1) is installed in the front installation position.

 Bolt, strut (impact absorber) to front axle carrier

*BA33.10-P-1003-01Q

34.2

Unscrew screws (18) and remove left and right radiator mount (6).

If the radiator package (1) is installed in the rear installation position.

 Installation: Make sure that the elastomer bearings (22) are seated correctly.

 Bolt, strut (impact absorber) to front axle carrier

*BA33.10-P-1003-01Q

35

Pull front axle (4) slightly toward rear and remove aluminum struts (7).

 Installation: Note the previously made markings when sliding in the aluminum struts (7).

36

Fully lower front axle (4).


Carefully lower front axle (4).
Otherwise adjacent components may be damaged.

37

Install in the reverse order.

38

Perform chassis alignment.

AR40.20-P-0200FR

 Engine mount, engine support (engine side)

Number

Designation

Model 257

BA22.10-P-1002-03N

Bolt, front engine mount to front axle carrier

M8

Nm

30

 Front axle carrier

Number

Designation

Model 257

BA33.10-P-1001-01Q

Bolt, front axle carrier to longitudinal member

Nm

180

 Front axle carrier

Number

Designation

Model 257

BA33.10-P-1002-01Q

Mount, support (strut)

Nm

110

 Front axle carrier

Number

Designation

Model 257

BA33.10-P-1003-01Q

Bolt, strut (impact absorber) to front axle carrier

Nm

23

 Air conditioning

Number

Designation

Model 257

BA83.30-P-1006-01R

Nut/bolt, refrigerant line to condenser

Nm

12