Disassemble/assemble differential

AR35.30-Y-0465IND

Disassemble/assemble differential

27.01.2020

Rear axle

400.756 in model 831.001/002/005

Disassemble drive head

1

Drive head unit

2

Special tool overhaul stand

3

Mounting bracket

4

Crown wheel pinion

5

Special tool flange holder 090 589 00 05 00

6

Split pins

7

Side bearing cap mounting bolts

9

Differential unit

8

Side adjuster nut/ring

Assemble

7

Side bearing caps

8

Side adjuster nut/ring

9

Differential unit

10

Side bearing adjusting rings threads

11

Special tool bearing adjuster 090 589 05 07 00

Inspect bearing pattern

Assemble drive head

6

Split pins

7

Side bearing caps

12

New oil seal

13

Flange nut

1

Drive head unit



Disassemble

 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

1

Remove drive head assembly from the vehicle.

AR35.10-Y-0010IND


Always be careful in handling gears or other sharp edge components.
To avoid injury.

2

Place the drive head unit (1) on the special tool overhaul stand (2) and mounting bracket (3).

 Assembly stand

*090589153100

3

Position drive head unit on the overhaul stand as shown in the illustration.

4

Measure the crown wheel pinion (4) backlash using magnetic stand and dial gauge.

AR35.31-Y-0550-25D

 Lock the pinion flange using the special tool flange holder (5).
Always check the backlash and note down the reading before dismantling the drive head unit. Always record tooth contact pattern at four points.

 Counterholder

*090589000500

5

Check and record the tooth contact pattern.

6

Remove the special tool flange holder (5) from the pinion flange.

 Counterholder

*090589000500

7

Remove the split pins (6) from the bearing adjuster nuts.

8

Remove both side bearing cap mounting bolts (7).

9

Unscrew both side adjuster nut/ring (8) using special tool bearing adjuster.

 Adjusting device

*090589050700

10

Remove the differential unit (9) from the drive head casing using suitable belt.


Be careful while removing the differential casing.
To ensure that the side bearing and outer race are not damaged.

11

Remove pinion housing.

AR35.30-Y-0469A

12

Disassemble pinion shaft.

AR35.30-Y-0459D

13

Disassemble crown wheel.

AR35.30-Y-0462D

Drive head inspection

14

Check the crown wheel and the pinion for damages on the teeth.

 Check for chipping of edges deep scoring, scuffing, excessive wear and improper teeth contact etc.

If necessary,



replace crown wheel and pinion as a set.

15

Check the crown wheel mounting holes and mating threaded holes in the differential housing for any damage.

If necessary,



replace crown wheel and pinion as a set.

16

Check the bearings of crown wheel and pinion.

 Check for any scoring, pitting, visible indentations and discoloration.

If necessary,



replace the bearing unit as a set.

17

Check differential housing inside for any abnormal wear on the thrust washer seating areas of the sun and star gears.

 Replace the either thrust washers or the housing based on extent of wear.

18

Check differential gears for any damages to the teeth.

 Check the internal splines of sun gear and star gear inner bore.

If necessary,



change the set of differential gear.

19

Check spider arms for any abnormal wear, scoring and discoloration.

If necessary,



change the set of differential gear.

20

Check adjusting ring threads and corresponding threads on the drive head of differential side bearings.

 Clean the threads and reuse.

If the damage is excessive,



replace drive head housing.

21

Check the bearing seating areas of pinion bearings and differential side bearings.

 Check for any rotation marks or any other damage in the drive head.

If necessary,



replace drive head housing.

22

Check the drive head seating area over the rear axle and pinion housing for any damages.

 Rectify seating area on the rear axle or drive head as per the requirement.

23

Check the companion flange.

 Check for any damage at the splines as well deep scoring marks at the oil seal contact area.

If necessary,



replace companion flange.

24

Inspect crown wheel and pinion match number.

AR35.31-Y-0550-25D

Cleaning procedure

25

The differential carrier unit must cleaned with cotton cloth.


Once removed from its housing, do not steam clean differential carrier unit.
As water can get trapped and lead to rust formation.

26

Disassemble the differential carrier unit completely and clean it with solvents.


Petrol is not an acceptable solvent.
Due to its extreme combustibility and its unsafe in the workshop environment.

 There are many suitable commercial solvents available. (Kerosene and diesel fuel are also acceptable).

27

Dry parts immediately.

 Smear with oil then cover the components with polyethylene to avoid dust entry.



Assemble

28

Assemble pinion shaft.

AR35.30-Y-0459D

29

Assemble crown wheel.

AR35.30-Y-0462D

30

Install pinion housing.

AR35.30-Y-0469A

31

Check the pinion housing bearing pre-load.

AR35.30-Y-0458-06B

32

Calculate required shim thickness and insert shims.

AR35.31-Y-0550-13D

33

Install the entire differential unit (9) with crown wheel to the drive head housing and remove the belt.



BB00.40-P-0235-01A

 Ensure the crown wheel teeth and pinion teeth face together.
Lubricate bearings during this assembly.

34

Apply oil to the differential side bearing adjusting rings threads (10) and install them.



BB00.40-P-0235-01A

 Ensure the bearing shells are properly seated.

35

Install differential side bearing cap (7) and hand tighten the mounting bolts 4 nos.

 Rotate the adjuster nut/ring and ensure the free movement over the threads.

36

Tighten the adjuster nut/ring behind the crown wheel till the crown wheel butts against the pinion teeth.

 Use special tool bearing adjuster (11).

 Adjusting device

*090589050700

37

Tighten the side adjuster nut/ring (8) in front side of the crown wheel.

 Tighten till the differential side bearings are properly seated and crown wheel is engage with the pinion.

38

Inspect crown wheel to pinion backlash.

AR35.31-Y-0550-25D

39

Adjust tooth contact pattern.

AR35.30-Y-0475-02B

Inspect and adjust, bearing pattern

40

Lubricate the crown wheel teeth with ocher for approximately a quarter of the circumference to make the bearing pattern visible.

 Ocher is a yellow-colored substance that dissolves in oil.
The solubility in oil necessary to prevent any damage occurring the differential gear at a later date, when it has been fitted in the axle housing.
Other agents can also be used, assuming they are soluble in oil and leave no residue.

41

Turn the pinion, using a crank on the drive flange.

42

Turn the crown wheel a few revolutions forwards and backwards in this way.

 On the lubricated section of the crown wheel, the bearing pattern become visible.

43

Observe the bearing patterns on a minimum of 4 places on the circumference of the crown wheel.

 With a light load, the bearing pattern of the forward flank in the middle of the flank over approximately 60% of the width tooth.
For the rear flank, the same applies with the difference that the bearing pattern is over approximately 40% of the tooth.

44

Observe bearing pattern of the forward flank and the rear flank.

 The bearing pattern must lie on approximately the same radius of the crown wheel.
The bearing patterns of the forward flank and rear flank then be on the same section of the tooth.

45

Ensure the bearing patterns must be approximately between the top and the foot of the tooth flanks.

46

Ensure the bearing patterns on both the forward flank and the rear flank do not run off the tooth flanks at any point.

 Ensure they also not lie too deep in the teeth.

If there is a difference in the positioning of the bearing patterns,



check whether the crown wheel is correctly position against the differential housing (check for burrs, chips etc).

If the bearing pattern is not correct,



check whether the fitting dimension of the pinion and the crown gear-to-pinion backlash are correctly adjust.

Assemble drive head

47

Tighten the side bearing cap mounting bolts (7) after obtaining the specified backlash and tooth pattern.

 Apply one bead of recommended sealant for each bolt across the threads.

 Side bearing cap mounting bolts

*BA35.30-Y-1001-03A

Loctite 262

*BR00.45-Z-1059-02A

48

Check crown wheel and pinion tooth contact pattern.

AR35.30-Y-0475-02B

49

Fit new split pins (6) into the bearing caps/adjusting ring.

 Avoid reuse the split pins to the bearing caps/adjusting ring.

50

Remove the old flange nut and flange from the pinion shaft.

51

Install new oil seal (12) to pinion housing using special tool seal installer.

 Drift

*090589661500

52

Install flange and flange nut (13) to pinion shaft.


Avoid reuse the pinion flange nut and pinion seal, replace with new component.
Cause damage.

 Hold the flange using special tool flange holder.
Apply one bead of recommended sealant to the pinion flange nut across the threads.

 Flange nut to pinion shaft

*BA35.30-Y-1002-03A

Loctite 262

*BR00.45-Z-1059-02A

 Counterholder

*090589000500

53

Remove the drive head unit (1) from overhaul stand.

AR35.10-Y-0010IND

 Prepare the drive head for installation to rear axle.

 Differential

Number

Designation

Rear axle 400.756 in model 831.001/002/005

BA35.30-Y-1001-03A

Side bearing cap mounting bolts

Torque

Nm

45

Angular torque



400

 Differential

Number

Designation

Rear axle 400.756 in model 831.001/002/005

BA35.30-Y-1002-03A

Flange nut to pinion shaft

Nm

67525

Repair materials

Number

Designation

Order number

BR00.45-Z-1059-02A

Loctite 262

Henkel AG & Co. KGaA
http://www.loctite.de