Differential Output Shaft Seal

RENEW

Fig.1:

Remove the rear brake disc (1, Fig.1).

Remove the five bolts (2, Fig.1) securing the output shaft bearing housing flange to the final drive. Withdraw the complete output shaft/bearing assembly and discard the O-ring (3, Fig.1). Clean the output shaft/bearing assembly.

Fig.1a:

Fig.2a:

Clamp the output shaft bearing housing between suitably protected jaws of a vice. Push back the lock washer tabs (1, Fig.2) and remove the bearing retaining nut (2, Fig.2) from the shaft using Service Tool SL 15 B (Fig.1a). Remove and discard the lock washer.

Fig.1a:

Withdraw the output shaft (6, Fig.2) from the output shaft bearing housing (8, Fig.2). Collect the inner bearing (3, Fig.2) and cone. Discard the collapsed spacer (4, Fig.2).

Fig.3a:

Note: If the outer bearing (5, Fig.2) remains on the shaft and pushes the oil seal (7, Fig.2) out of the output shaft bearing housing on withdrawal, remove it from the shaft using Service Tool SL47-3/1 in conjunction with the hand press 18G 47 (Fig.2a).

Fig.1a:

Pry the oil seal (7, Fig.2) from the output shaft bearing housing. Collect the outer bearing (5, Fig.2) and cone. Discard the oil seal. Using a suitable drift, gently tap the bearing cups out of the housing. Remove the output shaft bearing housing from the vice and carefully clean internally.

Note: When bearings are to be renewed, always replace complete bearings. Never fit new cone and roller assemblies into used cups.

Before fitting, new 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 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.

Fig.1b:

Press the cups of the replacement bearings into the housing, using a suitable press and adaptors to ensure that the cups are pressed fully home in the housing. Place the roller and cone assembly ofthe outer bearing (already greased) into position. Press the new oil seal into position (1, Fig.3a), ensuring that the spring-loaded sealing edge is adjacent to the bearing. Load the seal with grease between the sealing edges.

Fig.1:

Fig.1b:

Clamp the output shaft bearing housing between the protected jaws of the vice. Check that the four special bolts (4, Fig.1) for the brake disc are in position in the output shaft flange. Enter the shaft through the seal and outer bearing. Fit the bearing using Service Tools SL47-3/1 and SL47-3/2 and the hand press 18G 47 (Fig.1b).

Fit a new collapsible spacer. Fill the space between the bearings with Shell Spirax 90 oil before refitting the rollers and cone of the inner bearing. Fit a new lock washer on to the shaft. Place the nut on to the shaft, grease the face next to the washer and tighten finger-tight only.

Using Service Tool SL 15 B and a tommy-bar on the disc attachment bolts to oppose the torque, tighten the nut on the shaft just sufficiently to almost eliminate any play from the bearings. Torque required to turn the shaft should be 1.1 to 2.3 Nm (10-20 lbf/in.).

Further tighten the nut, very slightly (not more than a thirty-second of a turn or about 5 mm (3/16 in.) at the perimeter of the nut and re-check the torque required to turn the shaft. Continue to tighten the nut in very small increments, turning the shaft to seat the bearings and measuring the torque after each increment until the correct figure is reached.

CAUTION: If the torque required to turn the shaft exceeds by more than 2.3 Nm (20 lbf/in.) the torque recorded in the first check, dismantle the assembly, discard the collapsible spacer and rebuild with a new collapsible spacer.

It is not permissible to slacken off the nut after collapsing the spacer, as the bearing cones are then no longer rigidly clamped. Lock over the tab washers in two places to lock the shaft nut. Remove the assembly from the vice.

Fig.1:

Before fitting the output shaft assembly, ensure that the four disc flange bolts (4, Fig.1) are in position, and that a new O-ring (3, Fig.1) is fitted. Lightly oil the splines and outside of the bearing with final drive oil, and insert the output shaft assembly. Fit and torque tighten the securing bolts.

Refit the brake caliper and disc.

Check/adjust the camber angle of the rear wheels.

SERVICE TOOLS
18G 47 Hand press
18G 681 Torque screwdriver
SL 15 B Output shaft nut wrench
SL 47-3/1 Bearing remover/replacer
SL 47-3/2 Bearing remover/replacer

TORQUE FIGURES
Output shaft bearing housing to unit 81.5 - 93.5 Nm

OILS / SEALANTS / LUBRICANTS
Differential oil Shell Spirax Super 90