Differential (Visco) - Checking and Replacement
SECTION4
GROUP:
46
NO.
812
DATE:
Aug. 1996
Checking and replacement of visco-[1][2]differential Manual transmission only
850 R M/Y 1996-
REFERENCE: NONE
Checking and replacement of visco-[1][2]differential, 850 R
General information
AA
A new type of [1][2]differential has been introduced into production on the 850 R as from 1996 models, from the following chassis no.s:
Model Factory code: Chassis No.s:
854 2 311187
855 2 224334
This Service bulletin describes checking and replacing the new visco-[1][2]differential, P/N 9176152-8. It is only to be found in the 850 R.
This gives the driver the opportunity to enjoy the performance we have built into this model. With the visco-[1][2]differential, good roadholding characteristics are maintained even during sporty driving on winding sections of road.
The visco-[1][2]differential is located on the right drive shaft secured to the transmission differential with splines.
To create room for mounting the visco-[1][2]differential, the transmission clutch cover has been modified. The modified transmission is called M59.
Note!
For other work on the drive shafts and transmission, see: Service Manual, Manual Transmission M56, incl. clutch and drive shafts.
TP 4101201.
Checking friction in the visco-[1][2]differential
BA
Turn off engine while checking the visco-[1][2]differential.
Raise car on a lift so that front wheels hang freely.
Shift into first gear, turn the front right wheel by hand at a steady speed.
Use a torque wrench with slip meter.
The correct torque 60 - 100 Nm (44 - 74 ft.lbs).
Note!
If the car has been parked in extreme heat, the torque may be somewhat higher.
If too low a torque reading is given, the visco-[1][2]differential should be replaced according to BB.
Replacing the visco-[1][2]differential.
Replacing the visco-[1][2]differential
Special tools: 9995540, 9995562, 9995563
BB1
Removing the wheel and the ABS sensor
Raise the car on a lift.
Remove:
- right front wheel.
- brake hose bracket and ABS cable. Unhook the bracket.
- ABS sensor and hang up the sensor.
Note!
Do not separate the ABS sensor connector.
- drive shaft nut, use counterhold 999 5540-3. Knock the end of the drive shaft 10 - 15 mm (3/8" - 5/8") into the hub. Use a copper or rubber mallet.
BB2
Installing protective sleeve
Remove:
- nut to anti-roll bar link. Unhook the link.
- axle shaft/ball joint bolt. Disconnect the ball joint from the axle shaft and install protective sleeve 999 5562-7 to ball joint.
BB3
Removing drive shaft
Install retainer 999 5563-5 to hold down the link arm.
Press the drive shaft to its inner position. Twist and fold out the spring strut and remove the drive shaft from the hub.
Remove:
- drive shaft bearing cap.
- shaft by carefully pulling it straight out from the transmission so as not to damage the transmission sealing ring.
Note!
Hold onto the visco-[1][2]differential when removing the drive shaft.
BB4
Cleaning and checking
Place the drive shaft on a bench. Pull the visco-[1][2]differential off the shaft and remove the 0-ring from the drive shaft.
Clean the outer constant velocity joint splines and the hub of remnants of metal adhesive.
Check that the drive shaft spline joints are free of defects.
Check that the visco [1][2]differential cleaning surface is free of defects.
BB5
Installing
Oil in shaft end
Install:
- a new O-ring on the drive shaft
- the visco-[1][2]differential on the shaft
BB6
Installing the drive shaft
Install the drive shaft into the transmission
Note!
Hold onto the visco-[1][2]differential so that it does not fall off the drive shaft during installation.
Caution!
Take care to ensure that neither the sealing ring in the transmission or the bellows are damaged.
Install the drive shaft bearing cap and tighten to 25 Nm. (18 ft.lbs).
BB7
Installing drive shaft to hub
Apply metal adhesive 1161370-0 to the drive shaft hub splines.
Fold out and twist the spring strut and position the drive shaft in the hub.
Lubricate the drive shaft nut and install by hand.
The old nut can be reused.
Remove the holder from the link arm.
BB8
Installing link arm
Install:
- link arm/ball joint to axle shaft. Remove sleeve 999 5562-7. Make sure that the groove for the ball joint lug corresponds with the screw hole in the axle shaft. Use new locknut and tighten to 50 Nm (37 ft.lbs).
- link to the anti-roll bar. Use new locknut and tighten to 50 Nm (37 ft.lbs).
BB9
Tightening drive shaft nut
Tighten shaft nut.
Use counterhold: 999 5540-3 and protractor 951 2050-7.
Tighten to: 120 Nm (88 ft.lbs). Angle tighten 6O°.
Remove counterhold.
BB10
Installing ABS sensor
Install:
- bracket to the brakeline/ABS cable.
- ABS sensor onto axle shaft. Clean the sensor with a soft brush.
Note!
Make sure that the sensor seat is absolutely clean.
Tighten the sensor to 10 Nm (7.4 ft.lbs).
BB11
Installing wheel
- Tighten the wheel bolts lightly, then tighten diagonally to a final torque of 110 Nm (81 ft.lbs). Use torque socket 115 8147-7 if using a nut runner.
- Diagonal tightening and torquing are essential to avoid stressing the brake disc.
The torque socket is designed for tightening with a standard impact type, pneumatic nut runner delivering a torque of 250 - 350 Nm (185 - 258 ft.lbs).
WARRANTY STATEMENT: Claims may be submitted under the New Car Limited Warranty when a manufacturing defect is present using claim type: 01
Operation No. Labor description Time allowance
46636-2 Visco-[1][2]differential axle shaft, replacing 0.1 hr
46634-2 Friction in visco-[1][2]differential, checking 1.0 hr