Differential Output Shaft Seal

Remove output shaft assembly. Service and Repair

Clean assembly and clamp caliper mounting bracket between suitably protected jaws of vice.

Fig.16:

Fig.17:

Turn down tabs of lock washer (1, Fig.16) and remove nut from shaft. using spanner SL15A (1, Fig.17).

Remove and discard lock washer.

Withdraw output shaft from caliper mounting bracket. Collect inner bearing and cone and mark for correct reassembly.

Discard collapsed spacer.

Pry oil seal from caliper mounting bracket and discard. Collect outer bearing and cone.

Fig.14:

Remove caliper mounting bracket from vice and thoroughly clean internally. If outer bearing remains on shaft and pushes oil seal out of caliper mounting bracket on withdrawal, remove it from shaft using tool SL47-3/1, 47(1, Fig.18).

NOTE: Carefully inspect taper roller bearing components before refitting. If any fault is found in either bearing, replace both complete bearings. Never fit new cone and roller assemblies into used cups.

Fig.16:

Before fitting. bearings should be lightly greased, but it is most important that at least 4 cc of hypoid oil is added to the cavity between the bearings during assembly, and that the oil seal (2, Fig.16) is lubricated by packing the annular space between its sealing edges with grease. This prevents premature seal or bearing wear before oil flow begins from the axle centre.

Refitting (using original bearings)

Place roller and cone assembly of outer bearing (already greased) in position.

Press replacement oil seal into position, ensuring that spring-loaded sealing edge is adjacent to bearing. Load seal with grease between sealing edges.

Fig.1b:

Clamp caliper mounting bracket (3, Fig.16) between protected jaws of vice. Check that four special bolts (4, Fig.16) for brake disc are in position in output shaft flange and enter shaft through seal and fit the outer bearing using tools SL47-311, SL47-3/2 (1, Fig.19).

Fig.16:

Smear oil on portion of shaft in contact with seal. Fit new collapsible spacer (5, Fig. 16) and fill the space between bearings with Hypoid EP 90 oil before replacing rollers and cone of inner bearing and fitting new lock washer on shaft.

Place nut (6, Fig.16) on shaft, grease face next to washer and tighten finger tight only.

Using torque screwdriver 18G 681 and adaptor check torque required to turn shaft in caliper mounting bracket against resistance of the oil seal. Record the torque.

NOTE: Set screwdriver initially to 0.05 kgf/m (4 lbf/in.). Setting should then be progressively increased until torque figure is established at the point when shaft commences to turn.

Using spanner SL 15A and a tommy-bar at disc attachment bolts to oppose torque, tighten nut on shaft just sufficiently to almost eliminate play from bearings. Repeat torque check. Torque required to turn shaft should be unchanged, if it has increased, slacken nut very slightly and re-check.

Further tighten nut, very slightly (not more than a thirty-second of a turn about 5 mm (3/16 in.) at perimeter of nut and recheck torque required to turn shaft. If this torque exceeds by 0.05 to 0.10 kgf/m (4 to 8 lbf/in.) the torque recorded earlier, correct bearing pre-load has been achieved, otherwise continue to tighten nut in very small increments, turning shaft to seat hearings and measuring torque after each increment, until correct figure is reached.

CAUTION: If torque required to turn shaft exceeds by more than 0.10 kgf/m (8 lbf/in.) torque recorded initially, it is necessary to dismantle assembly, discard collapsed spacer and rebuild with new collapsible spacer. It is not permissible to slacken back nut after collapsing spacer as bearing cones are then no longer rigidly clamped.

Turn down tab washer in two places to lock nut and remove assembly from vice.

Refit output shaft assembly to final drive unit, Service and Repair