differential LAND ROVER DEFENDER 1996 Owner's Manual

51REAR AXLE AND FINAL DRIVE
4
OVERHAUL
37.UsingLRT-51-500and pressLRT-99-002,
remove inner bearing cone from pinion.
INSPECTION
38.Examine all components for obvious wear or
damage.
39.Bearing cones must be a press fit on their
locations, except drive pinion flange and bearing
which is a slide fit.
40.The crown wheel and pinion are supplied as a
matched pair and must not be interchanged
separately. A new crown wheel and pinion
matched pair may be fitted to an original gear
carrier casing if sound. original crown wheel and
pinion, if sound, may be fitted into a replacement
casing.
41.The two parts of differential unit casing are
matched and must not be replaced separately.
42.Discard and renew all thrust washers.
43.Differential housings with worn thrust washer
seatings must be replaced as a pair.
44.Examine differential case to crown wheel joint
face for burrs and damage which could lead to
crown wheel run-out when fitted.ASSEMBLE
Differential
45.Fit differential lower wheel and thrust washer to
differential case. See illustration following
instruction 23.
46.Fit dished thrust washers.
47.Fit cross-shaft and pinions.
48.Fit differential upper wheel and thrust washer.
49.Fit differential upper case lining-up marks.
50.Secure assembly with bolts using Loctite
'Studlock' grade CVX on threads and tighten
evenly and diametrically to
95 Nm (70 lbf/ft).
51.Fit crown wheel to differential casing. Use Loctite
'Studlock' grade CVX on fixing bolt threads and
tighten to correct torque.
52.Press on differential roller bearing cones less
shim washers, usingLRT-51-504, and leave to
one side until required for instruction 96.
53.Fit bearing cups to differential.
54.Fit differential unit and bearings to gear carrier
casing, and rotate unit to centralize bearings. Do
not fit bearing caps.

REAR AXLE AND FINAL DRIVE
5
OVERHAUL
55.Position a suitable dial gauge indicator on casing
with stylus registering on back face of crown
wheel.
56.Rotate differential and check total indicated
run-out on crown wheel back face. This must not
exceed 0,05 mm. If run-out is excessive, check
mating faces for dirt and damage; if necessary,
select a new radial position for crown wheel.
When satisfactory, continue with following check.
Differential bearing adjustment
57.Insert two levers between casing and differential
unit at one side.
58.Move differential unit fully to one side of casing;
do not tilt unit.
59.Rotate differential unit to settle bearings,
continue to lever differential to side, then zero
dial gauge indicator.
60.Lever assembly fully to other side of casing,
rotate unit to settle bearings, then note total
indicator reading.
61.Add 0,127 mm, for bearing pre-load, to total
noted in preceding instruction. The sum is then
equal to nominal value of shims required for
differential bearings. Shims are available in
range 0,07 mm, 0,12 mm, 0,25 mm and 0,76
mm. Select total value of shims required.
62.Remove differential unit and bearings and place
aside. Do not fit shim washers until subsequent
'Differential backlash' checks have been made,
instructions 96 to 102.Fit drive pinion
63.Select shim washers of same thickness value as
those removed from under pinion inner cup,
instruction 35, and place ready for fitting.
64.Position outer bearing replacerLRT-51-505,
detail 2, and outer bearing cup on press
LRT-99-502.
65.Locate assembly into pinion housing nose.
66.Place selected shim washers on to inner bearing
cup seating.
67.Position inner bearing cup in casing.
68.Position inner bearing replacerLRT-51-505,
detail 1, ontoLRT-99-502and secure with fixing
nut.
69.Hold still centre screw and turn butterfly lever to
draw in bearing cups.

51REAR AXLE AND FINAL DRIVE
6
OVERHAUL
70.Press inner bearing cone onto drive pinion using,
LRT-51-502details 1 and 2 and press
LRT-99-002.
71.Position pinion and bearing in casing; omit
collapsable spacer at this stage.
72.Fit outer bearing cone onto pinion.
73.Fit coupling flange and plain washer and loosely
fit flange nut.
74.Tighten coupling flange locknut to remove
end-float from pinion.
75.Rotate pinion to settle bearings and slowly
tighten flange locknut. Use a spring balance to
obtain a torque resistance of 11 Kgf/cm (18
lbf/in) to rotate pinion.
Drive pinion markings
76.Check that serial number marked on pinion end
face matches that marked on crown wheel.
77.The markings on end face adjacent to serial
number are of no significance during servicing.
78.The figure marked on end face opposite to serial
number indicates, in thousandths of an inch,
deviation from nominal required to correctly set
pinion. A pinion marked plus (+) must be set
below nominal, a minus (-) pinion must be set
above nominal. An unmarked pinion must be set
at nominal.
79.The nominal setting dimension is represented by
setting gauge block18G191PorLRT-54-503,
which is referenced from pinion end face to
bottom radius of differential bearing bore. The
latter gauge is illustrated following instruction 85.
Drive pinion adjustment
80.Ensure that pinion end face is free of raised
burrs around etched markings.
81.Remove keep disc from magnetized base of dial
gauge tool18G191.
82.Place dial gauge and setting gauge18G191Por
LRT-54-503on a flat surface and zero dial
gauge stylus on to setting gauge.

REAR AXLE AND FINAL DRIVE
7
OVERHAUL
83.Position dial gauge centrally on pinion end face
with stylus registering on lowest point on one
differential bearing bore. Note dial gauge
deviation from zeroed setting.
84.Repeat on other bearing bore. Add together
readings, then halve sum to obtain mean
reading. Note whether stylus has moved up or
down from zeroed setting.
Example 1
Reading obtained LH side.............. + 0.1524mm
Reading obtained RH side............. - 0.0762mm
Add + 0.1524mm - 0.0762mm = + 0.0762mm
Divide by 2 (0.0762 divided by 2)= 0.0381mm
Therefore subtract 0.0381mm from shim thickness
behind pinion inner bearing track.
Example 2
Reading obtained LH side............. + 0.1524mm
Reading obtained RH side............ - 0.2032mm
Add + 0.1524mm - 0.2032mm = + 0.0508mm
Divide by 2 (0.0508 divided by 2)= 0.0254mm
Therefore add 0.0254mm from shim thickness behind
pinion inner bearing track.
85.Where stylus has moved down (85a), amount is
equivalent to thickness of shims that must be
removed from under pinion inner cup to bring
pinion down to nominal position. Where stylus
has moved up (85b), amount is equivalent to
additional thickness of shims required to bring
pinion up to nominal position.
Illustration A. Using setting gauge18G191P.
Illustration B. Using universal setting block
LRT-54-503. This setting block has 3 setting heights.
Ensure that height marked 30.93 mm is used for this
differential.

REAR AXLE AND FINAL DRIVE
9
OVERHAUL Differential backlash checks
96.Pick up differential unit as left after instruction
52.
97.Fit differential unit and lever unit away from drive
pinion until opposite bearing cup is seated
against housing. Do not tilt unit.
98.Install a dial gauge on casing with its stylus
resting on back face of crown wheel. Zero the
gauge.
99.Lever differential unit to engage crown wheel
teeth in full mesh with drive pinion teeth. Do not
tilt unit.
100.Note total reading obtained on dial gauge.
101.From this figure subtract 0,25 mm to obtain
correct crown wheel backlash when fitted. The
result indicates value of shimming to be fitted
between differential case and bearing cone at
crown wheel side of differential.
102.Fit shim value determined in instruction 101,
taking shims from pack previously determined
during 'Differential bearing adjustment' checks,
instructions 57 to 62LRT-51-500details 1 and 2,
pressLRT-99-002, andLRT-51-504.
103.Fit remaining shims from instruction 101 to
opposite side of differential.LRT-51-501details
1 and 2, pressLRT-99-002, andLRT-51-504.
104.Fit differential unit with shims and bearings to
axle casing, using axle spreaderLRT-51-503
with pegs18G131F.
105.Remove axle spreader.106.Fit bearing caps in their correct position,
referring to relationship markings on caps and on
axle casing.
107.Tighten bearing caps fixings to
135 Nm (100
lbf/ft).
108.Mount a dial gauge on axle casing with stylus
resting on a crown wheel tooth.
109.Prevent drive pinion from rotating and check
crown wheel backlash which must be 0,15 to
0,27 mm. If backlash is not within specified
limits, repeat differential backlash checks,
instructions 96 to 102 looking for possible errors.
110.Fit differential cover and new gasket, coating
both sides of gasket with Hylomar PL 32M or an
equivalent non-setting sealant. Torque load for
fixings is
30 Nm (22 lbf/ft).
111.Reverse instructions 3 to 5 and coat threads of
hub driving member bolts with Loctite 'Studlock'
grade CVX and fit and tighten bolts evenly to
correct torque.
112.Fit rear axle assembly to vehicle
See Repair,
Rear axle
.
113.Replenish differential with recommended
lubricant
See LUBRICANTS, FLUIDS AND
CAPACITIES, Information, Recommended
lubricants and fluids
. After initial axle run,
check oil level and replenish as necessary to
filler/level plug hole.
114.Where major running parts have been replaced
during servicing, it is a recommended practice to
allow axle assembly to 'run in' by avoiding,
where possible, heavy loads and high speeds
during initial running.

REAR AXLE AND FINAL DRIVE
1
SPECIFICATIONS, TORQUE REV: 05/99 TORQUE VALUES
NOTE: Torque wrenches should be regularly checked for accuracy to ensure that all fixings are
tightened to the correct torque.
Nm
REAR AXLE
Pinion housing to axle case 41.......................................................................
Crown wheel to differential case 58................................................................
Differential bearing cap to pinion housing 90..................................................
Differential drive flange to drive shaft 47.........................................................
Bevel pinion nut 129........................................................................................
Lower link to axle 176......................................................................................
Pivot bracket ball joint to axle 176...................................................................

FRONT AXLE AND FINAL DRIVE
1
DESCRIPTION AND OPERATION DESCRIPTION
The welded steel front axle casing houses a separate
spiral bevel type differential unit, which is off-set to the
right of the vehicle centre line. The differential unit
drives the front wheels via the axle shafts and
constant velocity joints which are totally enclosed in
the spherical and swivel housings.The front wheels are pivoted on tape roller bearings at
the top and bottom of the swivel housing. The wheel
hubs on all axles are supported by two taper bearings
and driven by drive flanges which are splined to the
one piece, stub shaft/constant velocity joint.
Front axle hub and swivel housing
1.Axle casing
2.Ventilation pipe
3.Axle shaft
4.Wheel studs and hub
5.Stub axle
6.Wheel bearings
7.Inner and outer hub seals
8.Axle shaft seal
9.Hub lock plate, thrust washer and nuts
10.Brake disc
11.Drive flange
12.Shim washer and circlip13.Dust cap
14.Constant velocity joint/shaft
15.Thrust collar for CV joint
16.Roller bearing
17.Spacer
18.Circlip
19.Top and bottom swivel taper bearing
20.Top and bottom swivel pins
21.Spherical housing, seal and retainer
22.Swivel housing
23.Constant velocity shaft seal

54FRONT AXLE AND FINAL DRIVE
2
DESCRIPTION AND OPERATION Lubrication
The differential, swivel pin housing and wheel hubs
are indiviudally lubricated and separated by oil seals
(7) and (8), see J6267A, to prevent oil transfer across
the axle when the vehicle is traversing steep inclines.
The wheel bearings are lubricated with grease and the
swivel housing and differential with oil. On later
vehicles, identified by having only a filler plug in the
swivel housing, grease is used to lubricate the
housing assembly,
Ventilation
Ventilation of the differential is through a plastic pipe
(2) which terminates at a high level in the vehicle axle.
The swivel housings ventilate through axle shaft oil
seals (8) into the differential and the hub bearings
vent via the oil seals into the swivel housing.

FRONT AXLE AND FINAL DRIVE
1
FAULT DIAGNOSIS FAULT DIAGNOSIS
Complaint - Oil leaks
An external leak of lubrication can be caused by a
faulty internal seal. For example, if the seals which
separate the differential from the swivel housings are
faulty and the vehicle is operating or parked on an
embankment, oil may leak across the axle leaving one
swivel with a high level and the opposite swivel and
differential lacking lubrication.
See 'Description and Operation' for illustrations of oil
seal locations.
When investigating leaks or checking oil levels, it is
essential that all the lubrication is drained from any
housing with a high level and that the other levels are
checked.
Swivel oil should be checked for signs of grease
leaking from the hub bearings and oil contamination of
the hub grease.
Check that the axle ventilation system is clear, as a
blockage can cause internal pressure to force oil past
the seals.
If the vehicle is driven in deep water with defective oil
seals, water may contaminate the lubricants and when
checked, give a false impression that the housing has
been overfilled with oil.
Do not assume that a high oil level is due to over
filling or, that a low level is because of an external
leak.

FRONT AXLE AND FINAL DRIVE
1
OVERHAUL FRONT DIFFERENTIAL
Service repair no - 54.10.07.
Overhaul
NOTE: The front axle differential, for all
models, is the same as that fitted to the 90
rear axle and can only be serviced as a
complete assembly
See REAR AXLE AND FINAL
DRIVE, Repair, Differential assembly - 90
.
FRONT HUB
Service repair no - 60.25.14.
Overhaul
1.Remove hub assembly
See Repair, Front hub
assembly
.
2.Remove outer bearing.
3.Mark, for reassembly, relationship between hub
and brake disc, if original hub is to be refitted.
4.Remove 5 bolts and separate hub from brake
disc.
5.Drift out grease seal and inner bearing from hub
and discard seal.
6.Drift out inner and outer bearing tracks.
7.Clean hub and drift in inner and outer bearing
tracks.
8.Pack hub inner bearing with recommended
grease and fit to hub.
9.With lip side leading fit new seal to hub using
special toolLST 137seal replacer and drift18G
134. Drive in seal flush with rear face of hub.
Apply grease between seal lips.
10.Fit brake disc to hub, lining up to marks made
during dismantling. Applying Loctite 270, fit
retaining bolts. Tighten to
73 Nm (54 lbf/ft).
11.Grease and fit outer bearing to hub.
12.Fit hub assembly
See Repair, Front hub
assembly
.