wheel LAND ROVER DISCOVERY 2002 Owners Manual

AUTOMATIC GEARBOX - ZF4HP22 - 24
ADJUSTMENTS 44-21
ADJUST ME NTS
Cable - selector
$% 44.30.04
Check
1.Position vehicle on ramp.
2.Select position 'P'.
3.Loosen selector cable trunnion nut.
4.Ensure that gearbox selector lever is in 'P'
position, (fully forward) and tighten trunnion
nut.
5.Lower ramp.
Stall test
$% 44.30.13
Testing
1.Chock the wheels and fully apply the
handbrake.
2.Start the engine and run it until it reaches
normal operating temperature.
3.Apply the footbrake and select 'D'.
4.Fully depress the accelerator pedal and note
the tachometer reading. The figures should be
as given below. Do not carry out stall test for
longer than 10 seconds, and DO NOT repeat
until 30 minutes have elapsed.
lV8: 2200 to 2400 rev/min
lDiesel: 2600 to 2800 rev/min
5.A reading below 1300 rev/min indicates a
torque converter fault, ie stator free-wheel.
6.A reading between 1300 and 2200 rev/min (V8)
or between 1300 and 2600 rev/min (Diesel)
indicates reduced engine power.
7.A reading above 2400 rev/min (V8) or above
2800 rev/min (Diesel) indicates clutch slip.
NOTE: The figures quoted above were
measured at sea level with an ambient
temperature of 20
°C (68°F). At higher altitudes
or higher ambient temperatures, these figures
will be reduced.

REAR AXLE
51-2 DESCRIPTION AND OPERATION
Description
General
The rear axle consists of an axle casing with a differential unit attached to the right of the vehicle centre line. A wheel
hub is installed in each end of the axle casing and connected to the differential unit by a drive shaft.
Axle casing
The axle casing is of welded construction, with brackets on the casing exterior for attachment to the rear suspension.
A differential cover on the rear of the axle casing contains an oil level plug for checking and replenishment of the
differential unit lubricating oil. A magnetic drain plug is installed on the underside of the axle casing.
The interior of the axle casing is ventilated through a breather tube inserted in a red plastic sleeve in the top of the
casing. The open end of the breather tube is located between the chassis and the left rear wheelarch.
Differential unit
The differential unit is of the spiral bevel type, lubricated by splash oil. The unit consists of a differential carrier
attached to a pinion housing. In the pinion housing, the pinion is splined to a pinion flange which is secured with a bolt
and washer. An oil seal prevents leakage past the pinion flange.
Centralising peg
The centralising peg is a press fit in the centre of the pinion flange and provides a positive location for the rear
propellor shaft to ensure it is centralised with the flange.

REAR AXLE
DESCRIPTION AND OPERATION 51-3
Wheel hub
Section through wheel hub
1'O' ring
2Hub bearing
3Hub flange
4Wheel stud5Stake nut
6ABS sensor ring
7Drive shaft
8Axle casing
Each wheel hub consists of a hub flange pressed into a hub bearing.
The hub flange is splined to accept the outboard end of the drive shaft, which is secured to the hub flange with a stake
nut. Five studs are installed in the hub flange for the wheel nuts, and a threaded hole is provided for the brake disc
securing screw.
The outer race of the hub bearing is bolted to the end of the axle casing. An 'O' ring seals the joint between the outer
race and the axle casing to prevent leakage of differential lubricating oil. The hub bearing is a sealed unit which
contains twin opposed roller bearings, pre-packed with grease during manufacture. A toothed ABS sensor ring is
integrated into the inner race of the hub bearing. An opening in the outer race of the hub bearing accommodates the
ABS sensor.
Drive shaft
Each drive shaft consists of a solid rod, splined at both ends.

REAR AXLE
REPAIRS 51-5
REPAIRS
Differential - assembly
$% 51.15.01
Remove
1.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Drain oil from differential.

+ MAINTENANCE, PROCEDURES,
Front and rear axle.
3.If same components are to be refitted,
reference mark propeller shaft and mating
components.
4.Remove 3 nuts and bolts securing flexible
coupling to pinion flange. Release propeller
shaft and tie aside.
5.Using tool LRT-51-008, extract the centralising
peg from the pinion flange. Remove the
centralising peg from the tool.6.Remove LH and RH rear brake discs.

+ BRAKES, REPAIRS, Brake disc -
rear.
7.Disconnect each ABS sensor multiplug.
8.Release each harness from brake hose and
hose bracket.
9.Remove 4 bolts securing each rear wheel hub
to rear axle.
M51 0041B
5
4
M51 0056
LRT-51-008

REAR AXLE
51-6 REPAIRS
10.Release and remove wheel hubs and drive
shafts from rear axle. Remove and discard 'O'
rings from wheel hubs.
11.Remove 10 bolts securing differential to axle.
Release and remove differential from axle. Refit
1.Clean drive shafts, wheel hubs and wheel hub
locations in rear axle.
2.Using a suitable solvent, clean old RTV sealant
from differential and axle mating faces.
3.Apply RTV sealant to differential or axle mating
face.
4.Apply Loctite 243 to threads of differential
securing bolts.
5.Fit differential to axle, fit bolts and tighten to 55
Nm (41 lbf.ft).
6.Clean pinion flange and centralising peg.
7.Using a tubular drift, fit centralising peg to
pinion flange. Ensure that the large diameter
part of the centralising peg is below pinion
flange mounting surface.
8.Position propeller shaft and align reference
marks.
9.Fit nuts and bolts securing flexible coupling to
pinion flange and tighten to 76 Nm (56 lbf.ft)
10.Lubricate 2 new wheel hub 'O' rings with clean
differential oil.

+ CAPACITIES, FLUIDS AND
LUBRICANTS, Lubrication. Install 'O' rings on
wheel hubs.
11.Fit LH and RH drive shafts and wheel hubs to
rear axle. Fit wheel hub bolts and tighten to 100
Nm (74 lbf.ft).
12.Connect each ABS sensor multiplug and
secure harness to harness bracket and brake
hose.
13.Fit LH and RH rear brake discs.

+ BRAKES, REPAIRS, Brake disc -
rear.
14.Remove stand(s) and lower vehicle.
15.Fill differential with oil.

+ MAINTENANCE, PROCEDURES,
Front and rear axle.
M51 0042B

REAR AXLE
OVERHAUL 51-9
OVERHAUL
Differential assembly
$% 51.15.07
Disassembly
1.Remove differential assembly.
2.Secure differential assembly in a vice or stand.
3.Remove roll pins securing adjusting nuts, using
LRT 51-018-5 loosen adjusting nuts.
4.Reference mark bearing caps to aid assembly.
5.Remove bolts securing bearing caps and
remove caps.6.Remove crown wheel assembly and collect
bearing outer races.
7.Mark outer races to bearings to aid assembly.
8.Using LRT-51-003 to restrain pinion flange
remove bolt and collect washer.

REAR AXLE
OVERHAUL 51-11
16.Using a two legged puller and LRT 51-018/6,
remove the differential bearings.
17.Secure the crown wheel assembly in a vice.
18.Remove and discard 10 bolts securing the
crown wheel to carrier.
19.Carefully remove the crown wheel from the
carrier.20.Remove and discard roll pin securing carrier
cross shaft and remove cross shaft.
21.Rotate gears to the open part of carrier and
remove planet gears.
22.Remove sun gears.
Inspect
1.Clean and inspect all components for wear and
damage.
2.Fit planet gears and rotate to align cross shaft
holes.
3.Fit cross shaft, ensure roll pin hole is aligned.
4.Secure cross shaft with new roll pin.
5.Fit crown wheel to carrier, fit new bolts and
tighten to 60 Nm (44 lbf.ft).

REAR AXLE
OVERHAUL 51-13
22.Align setting gauge LRT-51-018/7 to setting
block, rock gauge to obtain minimum reading. If
reading is lower than required reading,
decrease shim size. If reading is higher than
required reading, increase shim size.
23.Using LRT-51-003 to restrain pinion flange,
remove bolt and washer. Remove pinion
flange.
24.Remove pinion, collect tail bearing and tail
bearing shim.
25.Remove pinion head bearing outer race and
shim. Discard shim. Ensure bearing race
recess is clean and free from burrs.
26.Fit calculated shim, and using LRT-51-018/4 fit
head bearing outer race.
27.Fit pinion, pinion tail bearing and tail bearing
shim.
28.Fit pinion flange and bolt and washer. Using
LRT-51-003 to restrain pinion flange, tighten
bolt to 100 Nm (74 lbf.ft).
29.Rotate pinion in both directions to settle
bearings.
30.Recheck pinion Torque to Turn, adjust if
necessary.
31.Recheck pinion head height.
32.Using LRT-51-003 to restrain pinion flange,
remove bolt and washer. Remove pinion
flange.
33.Discard bolt.34.Using LRT-51-010 fit pinion seal.
35.Ensure spacer and tail bearing are correctly
located.
36.Fit pinion, pinion flange and washer.
37.Fit new pinion flange bolt and tighten to 100 Nm
(74 lbf.ft).
38.Lightly oil differential bearings.
39.Ensure spring dowels are fitted in bearing caps.
40.Fit differential bearing outer races and locate
differential assembly into housing.
41.Fit bearing caps and tighten bolts to 10 Nm (7.5
lbf.ft).
42.Fit adjusting nuts, tighten crown wheel side nut
to 22 Nm (16 lbf.ft). Ensure opposing nut is
loose.
43.Position DTI to check crown wheel backlash.
Adjust opposing nut to obtain correct crown
wheel backlash.
44.Rotate pinion in both directions to settle
bearings.
45.Measure in 3 places to obtain correct crown
wheel backlash.
NOTE: Crown wheel backlash should be within
0.076 mm - 0.177 mm (0.003' - 0.007').
46.Align adjusting nuts to next roll pin slot, do not
loosen nuts to align slots.

REAR AXLE
51-14 OVERHAUL
47.Tighten bearing cap bolts to 90 Nm (66.5 lbf.ft).
48.Secure adjusting nuts with new roll pins.
49.Apply Prussian Blue to crown wheel teeth to
check tooth contact.
50.Rotate pinion several times to obtain full tooth
contact.51.A = Normal pattern, the drive pattern should be
centred on the gear teeth. The coast pattern
should be centred on the gear teeth but may be
towards the toe. There should be some
clearance between the pattern and the top of
the gear teeth.
52.B = Backlash correct, thinner pinion shim
required.
53.C = Backlash correct, thicker pinion shim
required.
54.D = Pinion shim correct, decrease backlash.
55.E = Pinion shim correct, increase backlash.
56.Note assembly Torque to Turn when checking
tooth contact. Total Torque to Turn should not
exceed 10.85 Nm (8 lbf.ft).
Reassembly
1.Fit differential assembly.

FRONT AXLE
54-2 DESCRIPTION AND OPERATION
Description
General
The front axle consists of an axle casing with a differential unit attached to the right of the vehicle centre line. A wheel
hub is installed in a steering knuckle at each end of the axle casing and connected to the differential unit by a drive
shaft.
Axle casing
The axle casing is of welded construction, with brackets on the casing exterior for attachment to the front suspension.
Yokes at each end of the casing incorporate upper and lower ball joints for attachment of the steering knuckles.
A differential cover on the front of the axle casing contains an oil level plug for checking and replenishment of the
differential lubricating oil. A magnetic drain plug is installed on the underside of the casing. An oil seal is installed in
each end of the axle casing to prevent leakage past the drive shafts.
The interior of the axle casing is ventilated through a breather tube inserted in a red plastic sleeve in the top of the
casing. The open end of the breather tube is located in the left rear corner of the engine compartment.
Differential unit
The differential unit is of the spiral bevel type, lubricated by splash oil. The unit consists of a differential carrier
attached to a pinion housing. In the pinion housing, the pinion is splined to a drive flange which is secured with a bolt
and washer. An oil seal prevents leakage past the drive flange.
Steering knuckle
The steering knuckles are mounted on upper and lower ball joints in the yokes at the end of the axle casing. A tension
collet, in the lower mounting point of each steering knuckle, accommodates manufacturing tolerances to enable the
correct tightening of both ball joints. Lugs are incorporated on the steering knuckles for attachment of the steering
system drag link and track rod.