ar3530a047004la

Checking friction torque of tapered roller bearings

Type ar · topic 35.30 · version 0100 · 2007-09-12

Applies to: REAR AXLE 748.785 in MODEL 8AB390.053 /054

Where it sits

Function group 2 Chassis › 35 Rear axle › 35.30 Final drive, drive shafts — Series 390 (models 053, 054)

EinPAS 17 Drivetrain/axle › 17.51 Rear axle › 17.51.65 Rear axle differential/axle through-drive — Series 390 (models 053, 054)

Also applies to engines/gearboxes: 748 785

AR35.30-A-0470-04LA

Checking friction torque of tapered roller bearings

Test and adjustment values for rear axle drive

Number

Designation

Rear axle
748.785

BE35.30-N-1002-01M

Friction torque of tapered roller bearings on drive pinion gear

Nm

1,1 to 2,3

Checking friction torque of tapered roller bearings

A35.30-0024-01

1 Wind a cord round the periphery of the pinion housing (6).

2 Attach spring test balance (12) to the cord.

3 Insert pinion housing (6) with drive pinion into a workshop press.

4 Place suitable sleeve (13) on the inner race of the tapered roller bearing.

5 Apply a load of approx. 14.5 t to the bearing.

6 Pull on spring test balance (12) until the pinion housing turns and in the process read off and note the measurement value for the tractive force.

7 Calculate the friction torque of the tapered roller bearings: RM = F x 0.5 x D

RM: Friction torque

F: Tractive force (measured value read off on spring balance)

D: Outside dia. of pinion housing (in area of cord)

If the specified values are not reached, remove drive pinion and reinstall with a suitable spacer ring.