Removal and Installation

REMOVAL

The final drive unit cannot be removed from the vehicle unless it is detached as part of the rear suspension unit.

Drain the oil from the unit to prevent any leakage from the breather, and invert the whole assembly onto a workbench.

Fig.8:

Remove the fourteen 1/2 in. AF bolts. nuts and 2 setscrews (1, Fig. 20) securing the bottom tie-plate to cross-beam and inner fulcrum brackets.

Fig.21:

Fig.22:

Remove the 11/16 in. AF nuts and washers (1, Fig.21) securing the dampers to the wishbone and drift out the retaining pins (1, Fig.22) recover the spacers and tie-down brackets.

Fig.21:

Slacken the clips (2, Fig.21) securing the inner universal joint shrouds and slide the shrouds outwards.

Fig.23:

Remove the four 11/16 in. AF self locking nuts (1, Fig.23) either side securing the drive shaft inner universal joint to the brake disc and output flange.

Fig.21:

Fig.24:

Fig.23:

Remove the 3/4 in. AF nut (3, Fig.21) from the inner wishbone fulcrum shaft and drift out the shaft (1, Fig.24) collecting the spacers, seals and bearings from the wishbone pivots (2, Fig.23).

Remove the drive shaft, hub and wishbone assembly from the rear suspension assembly.

Remove the camber shims from the drive shaft flange studs at the brake disc on both sides. Remove the spacer tubes from between the lugs of the fulcrum brackets and turn the suspension assembly over on the bench.

Disconnect the brake feed pipes from the calipers, seal the ends of the pipes and the ports in the calipers. Release the brake return springs from the operating levers.

Fig.4d:

Fig.26:

Cut the locking wire and remove the four 3/4 in. AF bolts (1, Fig.25) securing the final drive to the cross-beam and lift the cross-beam off the unit (Fig.26).

Fig.27:

Invert the unit and remove the locking wires and the 11/16 in. AF setscrews securing the fulcrum brackets to the final drive unit (1, Fig.27).

Remove the brackets, noting the position and number of shims at each attachment point.

Fig.28:

Cut the wires from the 5/8 in. AF caliper mounting bolts, remove the bolts and calipers (1, Fig.28). Remove the brake discs, noting the number of shims between the discs and the flanges.

Replace the shims and disc on one output shaft flange and secure with two nuts. Replace the caliper. Tighten the mounting bolts and check the centering and the run out of the disc. The centering tolerance is ± 0.25 mm (0.010 in.), this can be rectified by transferring shims from one side of the disc to another. The disc run out should not exceed 0.15 mm (0.006 in.).

INSTALLATION

Tighten the caliper bolts to a torque of 6.78-7.60 kgf/m 66.4 - 74.5 Nm (49 - 55 lb/ft). Repeat the above operations on the opposite side. Remove the nuts from both discs.

Place the cross-beam over the final drive, align and replace the bolts and tighten to the correct torque and wire lock 10.4 kgf/m, 101.68 Nm (75 lb/ft). Slacken the brake feed pipes at the centre union, unseal the brake pipes and the ports in the caliper, align and fit the pipes and tighten the unions.

Replace the handbrake lever return springs and invert the assembly on the bench. Position the fulcrum brackets against the final drive unit and locate each bracket loosely with two setscrews. Replace the shims between the fulcrum brackets and the final drive unit.

Tighten the setscrews and wire lock. Refit the camber shims to the drive shaft studs on one side. Fit the drive shaft on to the studs and loosely fit the nuts, and then tighten fully. Replace the spacer tube between the lugs of the fulcrum bracket.

Clean, inspect and grease the lower wishbone bearings, thrust washer etc. Fit new seals and offer up the wishbone fulcrum bracket lugs and locate with dummy shafts.

Fig.29:

Tool No. JD14 (1, Fig.29).

Take great care not to displace any component during this operation. Drift the dummy shafts from the fulcrum bracket with the fulcrum shaft. Restrain the dummy shafts to prevent spacers or thrust washers dropping out of position.

Tighten the fulcrum shaft nuts to a torque of:

Inner = 61.0 - 67.8 Nm. 6.23-6.91 kgf/m (45 - 50 lb/ft).
Outer = 131 - 145 Nm. 13.4-14.8 kgf/m (97 - 107 lb/ft).

Reposition the drive shaft shroud and secure it with the clip. Line up the damper lugs with the wishbone bosses and replace the damper shaft, including the spacer and tie down bracket and tighten the nuts to a torque of 43.4 - 48.8 Nm, 4.43-4.97 kgf/m (32 - 36 lb/ft).

Replace the wishbone, drive shaft and damper shaft on the opposite side. Replace the bottom tie-plate and tighten the bolts and setscrews.

Replace the rear suspension unit.

Check the rear wheel camber.

Bleed the brakes and fill the final drive with oil as necessary.

NOTE: Use Shell Super Spirax 90 or BP Gear Oil 1453 if new gears have been fitted; otherwise use a recommended refill or top up oil as specified.