Differential Assembly: Service and Repair
REMOVAL AND INSTALLATION OF REAR AXLE CENTER PIECE WITH REAR AXLE SHAFTSRemoval
1 Drain oil on rear axle.
2 Vehicles without starting torque compensation, unscrew caliper at the right and hang up by means of hook.
On vehicles with starting torque compensation, disconnect brake cable control, unscrew bracket on wheel carrier, remove rubber sleeve and push cover back.
3 Loosen hex bolt (M 12) of 1st version on both sides or hex bolt (M 8) with spacing sleeve and clamping disc of 2nd version for attaching rear axle shaft to rear axle shaft flange and remove.
4 If required, force rear axle shaft out of rear axle shaft flange by means of assembly fixture.
Attention! When removing assembly tool be sure to hold rear axle shaft in place. Do not let rear axle shaft drop down, since this would damage the housing of the synchromesh joint and make it leak.
If the rear axle shaft cannot be removed in spite of being fully telescoped, loosen rubber bearing from frame floor and rear center piece from rear axle carrier, Lower center piece and swivel to one side. Then remove rear axle shaft from rear axle shaft flange.
Do not loosen shock absorbers since they are required to hold axle.
5 Remove exhaust system (49-100).
6 Unscrew shielding plate.
7 Loosen lock nut and unscrew propeller shaft intermediate bearing on frame floor.
8 Unflange propeller shaft from rear axle and push forward out of concentric alignment.
9 Vehicle with ABS
a Loosen hex. socket screw (35) and remove rpm sensor (34) from rear axle housing.
Attention! Protect rpm sensor against damage. Do not put cable under tensile stress.
10 Support rear axle housing with a vehicle jack or a pitlift and top.
11 Unscrew rear rubber bearing on frame floor.
12 Lower vehicle jack or pitlift until self-locking hex nuts are accessible. Loosen brake cable control attachment at the left on frame floor (model 116).
13 Unscrew rear axle center piece from rear axle carrier (arrow)
14 Lower rear axle center piece and remove together with rear axle shafts.
Attention! When transporting rear axle center piece with rear axle shafts make sure, that the rear axle shafts are not falling down, since this would result in damage and leaks to the housings of the both inner synchromesh joints.
15 Unscrew rubber bearing from rear axle center piece.
16 Check rubber bearing and renew, if required.
Installation
17 Attach rubber bearing to rear axle center piece. Tighten hex bolts or hex socket bolts to 120 Nm.
18 Place rear axle center piece with rear axle shafts on vehicle jack top and move into installation position.
19 Introduce rear axle shafts into rear axle shaft flange by means of assembly fixture. Remove assembly fixture.
20 Lift rear axle center piece and attach to rear axle carrier. Prior to positioning self-locking hex. nuts, mount washer. Tighten self-locking nuts to 100 Nm.
Attention! Be sure to replace self-locking nuts.
21 Mount hex. screw M 8 for attaching rear axle shaft to rear axle shaft flange on 3rd version with clamping disc and spacing sleeve and tighten to 30 Nm.
Attention! Renew clamping disc after one-time use. Provide clamping disc (79a1 with oil in range of screw head.
22 Lift rear axle center piece up to frame floor and attach rubber bearing to frame floor. Tightening torque of hex bolts 25 Nm. Tightening torque of self-locking hex bolts 30 Nm.
Attention! Use self-locking hex bolts only once.
23 Attach propeller shaft to flange.
24 Attach propeller shaft intermediate bearing, but do not yet tighten.
25 Vehicles with ABS
Note: Prior to installation, make sure that no metallic foreign particles are located on magnetic edge of rpm sensor.
a Replace 0-ring (36) on rpm sensor (34).
b Insert rpm sensor (34) into rear axle housing (45), making sure that the 0-ring is not damaged.
Note: Use self-locking hex. socket screw only once.
c Attach rpm sensor to rear axle housing by means of hex. socket screw (35).
26 On rear axles without starting torque compensation, mount caliper (1) with new locking plate or self-locking hex bolts and tighten to 90 Nm (9 kpm).
On rear axles with starting torque compensation, mount bracket for brake cable control to wheel carrier. Slip on cover and rubber sleeve. Attach cable control and adjust parking brake.
27 Fill oil into rear axle at filler hole up to overflow.
28 Tighten lock nut on propeller shaft to 30-40 Nm.
29 Tighten propeller shaft intermediate bearing.
30 Mount shielding plate.
31 Install exhaust system.