brake LAND ROVER DISCOVERY 2002 Manual Online

TRANSFER BOX - LT230SE
41-16 DESCRIPTION AND OPERATION
Functionality – Vehicles from 03 model year only
The differential lock must be engaged for 2 wheel rolling road testing. It will also be necessary to disconnect the
propeller shaft from the transfer box output shaft driving the axle whose wheels are NOT on the rolling road. In
addition, the ETC system must be deactivated by either, removing a fuse (10A fuse 28 in the passenger compartment
fusebox, labelled ABS) or disconnecting the ABS modulator pump. This must be done with the ignition switched off.
Note that the SLABS ECU may record a system fault.
The lock can be engaged or disengaged using the selector lever. Vehicles not fitted with a differential lock can be
identified by a high/low range selector lever with no differential lock functionality and the cover and selector shaft
(arrowed), not visible on the front output housing.
WARNING: VEHICLES NOT FITTED WITH A DIFFERENTIAL LOCK MUST NOT BE TESTED ON A ROLLING
ROAD WHERE THE ROLLERS ARE DRIVEN BY THE VEHICLE.
Differential lock warning lamp switch - if fitted - Vehicles up to 03 model year
A differential lock warning lamp switch connected to the SLABS ECU and operated by movement of the selector fork
and shaft is screwed into the top of the output housing. The switch connects to earth when the differential lock is
engaged.
Differential lock warning lamp switches - if fitted - Vehicles from 03 model year
Vehicles from 03 model year are fitted with two differential lock warning lamp switches.
One switch is of a new design and is fitted into the top of the front output housing in the same position as on previous
models. The switch is connected to the SLABS ECU and is operated by movement of the selector fork and shaft.
The second switch is located in a threaded hole on the forward face of the front output housing. The switch is also
connected to the SLABS ECU and is operated by movement of the selector shaft.
Both switches have an aluminium washer which seals the switch to the casing and also sets the switch position,
removing the requirement for a setting procedure.
Both switches are connected in parallel to earth when the differential lock is engaged. This earth is sensed by the
SLABS ECU which illuminates the differential lock warning lamp in the instrument pack.
Differential lock warning lamp - Vehicles up to 03 model year – if fitted
The differential lock warning lamp is located in the instrument pack and provides a warning to the driver when the
ignition is switched on that the differential lock is engaged. The warning lamp illuminates in a Red colour.
With the lock engaged, the traction control and electronic brake distribution warning lamps will also be illuminated.
Disengagement of the differential lock should be carried out with the ignition switched off. The warning lamps must
be extinguished when the ignition is switched on again.
Differential lock warning lamp – vehicles from 03 model year – if fitted
The differential lock warning lamp is located in the instrument pack and provides a visual warning to the driver, when
the ignition is on, the differential lock is engaged. The warning lamp illuminates in an amber colour.
When the lock is engaged, the warning lamp is illuminated and the instrument pack sounder emits three audible
chimes. When the lock is disengaged, the warning lamp is extinguished and the instrument pack sounder emits three
audible chimes.
Rear output housing
The rear output housing carries the output shaft and flange. A cable operated transmission brake is attached to the
housing, the brake drum being attached to the output flange.
The rear output shaft is supported in the housing by a single bearing and is splined into the differential rear sun gear.

TRANSFER BOX - LT230SE
41-24 REPAIRS
Transfer box - Diesel
$% 41.20.25.99
Remove
1.Remove front exhaust pipe.

+ MANIFOLDS AND EXHAUST
SYSTEMS - Td5, REPAIRS, Pipe - front.
2.Raise vehicle on ramp.
3.Drain transfer box oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
4.Remove 3 nuts securing intermediate silencer
to tail pipe.
5.Release silencer from mounting rubbers.
6.Remove silencer and discard gasket.
7.Remove front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
8.Remove rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.9.Remove handbrake drum retaining screw and
remove drum.
10.Remove 4 bolts from handbrake back plate,
release back plate and tie aside.
11.Remove clevis pin securing high/low ratio
selector cable to selector lever, remove 'C' clip
and release outer cable from abutment bracket.

TRANSFER BOX - LT230SE
41-26 REPAIRS
Refit
1.Fit new input shaft oil seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Oil seal - input shaft.
2.Clean transfer box to gearbox mating faces.
3.Raise transfer box on jack and align to guide
studs LRT-41-009.
4.Clean transfer box to gearbox bolt threads.
5.Apply Loctite 290 to bolt and stud threads.
6.Fit and lightly tighten 2 bolts and nut securing
transfer box to gearbox. If new stud is to be
fitted, apply Loctite 290 to stud threads and
tighten to 45 Nm (33 lbf.ft).
7.Remove guide studs, fit and lightly tighten
remaining 3 bolts.
8.Tighten bolts and nut by diagonal selection to
45 Nm (33 lbf.ft).
9.Position gearbox RH mounting and tighten
bolts to 85 Nm (63 lbf.ft).
10.Tighten gearbox RH mounting nut to 48 Nm
(35 lbf.ft).
11.Remove 4 bolts securing support plate to
gearbox jack.
12.Remove 4 bolts securing support plate LRT-99-
010 to transfer box and remove plate.
13.Clean bottom plate bolt threads.
14.Apply Loctite 290 to threads of 4 bottom plate
bolts.
15.Fit 4 bolts securing bottom plate to transfer box
and tighten to 25 Nm (18 lbf.ft).
16.Position breather pipe and secure to bulkhead
clip.
17.Connect multiplug to reverse light switch.
18. If fitted - Connect Lucars to differential lock
switch.
19.Fit multiplug and cable tie to transfer gearbox
bracket. 20.Position high/low ratio selector cable and
secure with clevis pin.
21.Clean handbrake and mating face.
22.Position handbrake back plate and tighten
bolts to 75 Nm (55 lbf.ft).
23.Clean handbrake drum.
24.Fit handbrake drum and tighten retaining
screw.
25.Fit front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
26.Fit rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
27.Clean exhaust silencer and mating face.
28.Position silencer, fit new gasket , connect
mounting rubbers and tighten nuts to 40 Nm
(30 lbf.ft).
29.Refill transfer box with oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
30.Fit front exhaust pipe.

+ MANIFOLDS AND EXHAUST
SYSTEMS - Td5, REPAIRS, Pipe - front.

TRANSFER BOX - LT230SE
REPAIRS 41-27
Transfer box - V8
$% 41.20.25.99
Remove
1.Remove front exhaust pipe.

+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Front pipe.
2.Drain transfer box oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
3.Remove 8 bolts securing rear cross member
and remove cross member.
4.Remove 3 nuts securing intermediate silencer
to tail pipe.
5.Release silencer from mounting rubbers,
remove silencer and discard gasket.
6.Remove front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
7.Remove rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.8.Remove handbrake drum retaining screw and
remove handbrake drum.
9.Remove 4 bolts from handbrake back plate,
release back plate and tie aside.
10.Remove clevis pin and 'C' washer securing
high/low ratio selector cable to selector lever
and release cable from abutment bracket.

TRANSFER BOX - LT230SE
REPAIRS 41-29
22.Remove 4 bolts and nut securing RH mounting
to body and transfer box.
23.Remove nut securing LH mounting to body.
24.Raise gearbox and remove RH mounting.
25.With assistance, remove transfer box from
gearbox.
26.Remove input shaft oil seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Oil seal - input shaft.
Refit
1.Fit new input shaft oil seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Oil seal - input shaft.
2.Clean transfer box to gearbox mating faces.
3.Raise transfer box on jack and align to guide
studs LRT-41-009.
4.Clean transfer box to gearbox bolt threads.
5.Apply Loctite 290 to bolt and stud threads.
6.Fit and lightly tighten 2 bolts and nut securing
transfer box to gearbox. If new stud is to be
fitted apply Loctite 290 to threads of stud
and tighten to 45 Nm (33 lbf.ft)
7.Remove guide studs, fit and lightly tighten 3
bolts.
8.Tighten bolts and nut by diagonal selection to
45 Nm (33 lbf.ft.
9.Position gearbox RH mounting and tighten
bolts to 85 Nm (63 lbf.ft).
10.Tighten gearbox RH mounting nut to 48 Nm
(35 lbf.ft).
11.Fit nut to LH mounting and tighten to 48 Nm (35
lbf.ft).
12.Remove 4 bolts securing support plate to
gearbox jack.
13.Remove 4 bolts securing support plate LRT-99-
010 to transfer box and remove plate.
14.Clean threads of bottom plate bolts.
15.Apply Loctite 290 to threads of bolts.
16.Fit 4 bolts securing bottom plate and tighten to
25 Nm (18 lbf.ft).
17.Using new washers position breather pipe and
tighten banjo bolt.
18.Connect multiplug to transfer box neutral switch
and secure harness. 19. If fitted - Connect Lucars to differential lock
switch.
20.Connect multiplug and Lucars to reverse lamp
switch and oil temperature sensor.
21.Position high/low ratio selector cable and
secure with 'C' washer and clevis pin.
22.Secure cable to fuel pipes with new cable ties.
23.Clean handbrake back plate and mating face.
24.Position handbrake back plate, fit bolts and
tighten to 75 Nm (55 lbf.ft).
25.Clean handbrake drum.
26.Fit handbrake drum and tighten retaining
screw.
27.Fit front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
28.Fit rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
29.Clean exhaust silencer and tail pipe mating
faces.
30.Position silencer and secure on mountings,
using a new gasket align to tail pipe, fit nuts
and tighten to 25 Nm (18 lbf.ft).
31.Position rear cross member, fit bolts and
tighten to 26 Nm (19 lbf.ft).
32.Refill transfer box with oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
33.Fit front exhaust pipe.

+ MANIFOLDS AND EXHAUST
SYSTEMS - V8, REPAIRS, Front pipe.

TRANSFER BOX - LT230SE
41-34 REPAIRS
Seal - rear output shaft
$% 41.20.54
Remove
1.Remove rear propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - rear.
2.Loosen brake shoe adjuster bolt.
3.Remove screw securing handbrake drum. 4.Remove handbrake drum.
5.Restrain transfer box drive flange using tool
LRT-51-003. Remove and discard drive flange
nut, remove and discard steel and felt washers.
6.Using tool LRT-99-500 if necessary, remove
drive flange from transfer box.
7.Remove seal from transfer box.
Refit
1.Clean seal mating faces.
2.Lubricate seal with gearbox oil.

TRANSFER BOX - LT230SE
REPAIRS 41-35
3.Fit new seal using tool LRT-41-012.
4.Position drive flange, fit new felt and steel
washers.
5.Position tool LRT-51-003 and tighten new
drive flange nut to 148 Nm (109 lbf.ft).
6.Position handbrake drum and tighten screw.
7.Tighten brake shoe adjuster bolt to 25 Nm (18
lbf.ft) then loosen one and a half turns.
8.Check that brake drum is free to rotate.
9.Fit propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
10.Top-up transfer box oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
Gasket - rear output shaft housing
$% 41.20.55
Remove
1.Drain transfer gearbox oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
2.Remove rear output shaft seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Seal - rear output shaft.
3.Mark output shaft housing to main casing for
assembly purposes.
4.Note position of shoulder bolt, remove 6 bolts
securing housing to main casing.
Refit
1.Clean output shaft housing, mating face on
main casing and sealant from bolt threads.
2.Apply sealant, Part No. STC 3254 to mating
flange on output shaft housing.
3.Fit output shaft housing to main casing.
4.Apply Loctite 290 to bolt threads.
5.Fit output shaft housing bolts and tighten by
diagonal selection to 45 Nm (33 lbf.ft).
6.Fit rear output shaft seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Seal - rear output shaft.
7.Fill transfer gearbox with oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.

TRANSFER BOX - LT230SE
41-50 OVERHAUL
2.Secure rear half of differential carrier in a soft
jawed vice.
3.Fit each planet gear to its respective cross
shaft, fit new dished thrust washer to each
gear.
4.Fit cross shafts, planet gears and dished thrust
washers in rear half of carrier.Ensure that
cross shafts are fitted correctly. Do not fit
the sun gear into the rear half carrier at this
stage.
5.Fit retaining ring.
6.Fit a 1.05 mm (0.04 in) thrust washer to sun
gear from front half of carrier. Position gear in
front half of carrier.
7.Ensuring that assembly marks are aligned, fit
both halves of carrier together.
8.Fit the differential carrier bolts and, working in a
diagonal sequence, tighten the bolts to 60 Nm,
(44 lbf.ft).9.Insert the front output shaft into the front half of
the carrier and check that the gears rotate
freely.
10.Fit output flange on to the splines of the output
shaft, but do not fit flange nut at this stage.
11.Fit transmission brake drum to output flange
and secure the drum using 2 nuts.
12.Secure a length of cord around the drum and
attach one end of the cord to a spring balance.
13.Pull on the spring balance and note the load at
which the brake drum starts to turn. Used
gears should rotate smoothly, while new
gears will have a 'notchy' feel as they rotate.
14.Compare the figure obtained with the following.
lUsed gears = 0.45 kg (1.0 lb)
lNew gears = 1.72 kg (3.8 lb)
15.If the load to turn figure is below the specified
limits, proceed as follows.
16.Remove the front output shaft and brake drum.
17.Remove the 8 bolts securing the two halves of
the differential carrier
18.Separate the differential carrier and remove the
sun gear and thrust washer from the front half.
19.Select a thicker thrust washer from the range
available. 5 different thrust washers are
available, rising in increments of 0.10 mm
(0.004 in) from 1.05 mm to 1.45 mm (0.04 to
0.06 in).
20.Repeat steps 7 to 19 as necessary until the
load to turn figure is as specified
21.When specified load to turn is obtained,
proceed as follows.
22.Remove the front output shaft and brake drum.
23.Remove the 8 bolts securing the two halves of
the differential carrier
24.Separate the differential carrier and remove the
sun gear and thrust washer from the front
half.Retain the selected thrust washer with
its sun gear.

TRANSFER BOX - LT230SE
OVERHAUL 41-51
25.Remove retaining ring, then remove the planet
gears and cross shafts.
26.Fit a 1.05 mm (0.04 in) thrust washer to sun
gear from rear half of carrier. Position gear in
rear half of carrier.
27.Fit planet gears, cross shafts and dished thrust
washers to rear half of carrier. Ensure that
cross shafts are fitted correctly. Do not fit
the sun gear into the rear half carrier at this
stage.
28.Fit retaining ring.
29.Ensuring that assembly marks are aligned, fit
both halves of carrier together.
30.Fit the differential carrier bolts and, working in a
diagonal sequence, tighten the bolts to 60 Nm,
(44 lbf.ft).31.Invert the assembly in the vice, insert the rear
output shaft into the rear half of the carrier and
check that the gears rotate freely.
32.Fit output flange on to the splines of the output
shaft, but do not fit flange nut at this stage.
33.Fit transmission brake drum to output flange
and secure the drum using 2 nuts.
34.Carry out the load to turn check, using the same
method as for the front half carrier. Record the
shim thickness when the load to turn is correct.
35.Fit the sun gear and selected thickness shim to
the front half carrier.
36.Ensuring that assembly marks are aligned, fit
both halves of carrier together.
37.Fit the differential carrier bolts and, working in a
diagonal sequence, tighten the bolts to 60 Nm,
(44 lbf.ft).
38.With differential assembled, fit rear output shaft
and brake drum, then check overall load to turn.
This should be approximately the same as the
combined load to turn figure of both front and
rear half carriers.
lUsed gears = 0.90 kg (2.0 lb)
lNew gears = 3.44 kg (7.6 lb)

AUTOMATIC GEARBOX - ZF4HP22 - 24
DESCRIPTION AND OPERATION 44-5
1Release button
2Mode switch
3Electrical connector
4Interlock solenoid (where fitted)
5Base6Gasket
7Securing bolt
8Lever
9Cover
10Position indicators
The selector lever assembly consists of a lever and a cover attached to a base. The base is located on a gasket and
secured to the transmission tunnel. The lever is hinged to the base. A latch in the lever engages with detents in the
base to provide the lever positions P, R, N, D, 3, 2, 1. The latch is disengaged by pressing a release button on the
lever knob. Except for lever movement between positions D and 3, the button must be pressed before the lever can
be moved. In some markets, vehicles incorporate an interlock solenoid at the bottom of the lever, which prevents the
lever being moved from P unless the ignition switch is in position II and the foot brake is applied. If the battery
becomes flat, the interlock system will prevent selector lever movement and removal of the ignition key.
The cover incorporates lever position indicators and the mode switch. The lever position indicators illuminate to show
the position of the selector lever. Illumination is controlled by the Body Control Unit (BCU). The mode switch is a non-
latching hinged switch that, when pressed, connects an earth to the EAT ECU to request a change of mode.
An electrical connector at the rear of the cover connects the selector lever assembly to the vehicle wiring.
Selector cable
The selector cable is a Bowden type cable that connects the selector lever assembly to a selector lever on the
gearbox. 'C' clips secure the ends of the outer cable to brackets on the selector lever assembly and the selector lever.
The inner cable is adjustable at the connection of the inner cable with the gearbox selector lever.