ECU LAND ROVER DISCOVERY 2002 Workshop Manual

MANUAL GEARBOX - R380
OVERHAUL 37-49
Cover - front
$% 37.12.33.01
Disassembly
1.Remove retaining peg and remove release
bearing.
2.Remove bolt securing clutch release fork,
remove retaining clip and remove clutch
release fork.
3.Remove 2 bolts securing release bearing
sleeve and remove bearing sleeve. 4.Remove 6 bolts securing clutch housing and
remove clutch housing.
5.Remove and discard 6 bolts securing oil seal
housing.
6.Remove oil seal housing.
7.Using a soft metal drift, carefully remove input
shaft front bearing track from housing.
8.Remove oil seal from housing, discard seal.

MANUAL GEARBOX - R380
37-50 OVERHAUL
Reassembly
1.Using a suitable solvent cleaner, clean seal
housing mating faces.
2.Clean seal recess, bearings and bearing
races.
3.Lubricate new oil seal and fit using a suitable
mandrel into housing.
4.Fit input shaft front bearing track using a press
and suitable mandrel.
5.Apply sealant, Part No. STC 4404 to seal
housing, fit new bolts and tighten by diagonal
selection to 25 Nm (18 lbf.ft).
6.Clean clutch housing mating faces, dowels and
dowel holes.
7.Position clutch housing, fit bolts and tighten to
75 Nm (55 lbf.ft).
8.Clean release bearing sleeve mating faces,
dowel and dowel holes.
9.Position release bearing sleeve, fit bolts and
tighten to 25 Nm (18 lbf.ft).
10.Examine clutch release fork pivot points for
wear and replace as required.
11.Apply a smear of Molybdenum disulphide
grease to pivot points and position release fork.
12.Fit retaining clip ensuring it locates over pivot
point washer, fit bolt to release fork and tighten
to 10 Nm (7 lbf.ft).
13.Clean release bearing and bearing sleeve
mating faces.
14.Apply smear of Molybdenum disulphide grease
to release bearing sleeve.
15.Fit release bearing and secure with retaining
peg.

TRANSFER BOX - LT230SE
41-14 DESCRIPTION AND OPERATION
Transfer box interlock solenoid - Automatic gearbox vehicles
An interlock solenoid is fitted for North America and Japan. The solenoid is located on the top of the transfer box main
casing on vehicles up to 03 model year or on the selector lever assembly on vehicles from 03 model year. The
solenoid is connected to the transfer box relay which, in turn, is controlled by the IDM. The purpose of the solenoid is
to prevent neutral being selected on the transfer box when the ignition key is removed, thereby locking the box in
either high or low ratio.
Mainshaft input gear
The gearbox output shaft is splined into the mainshaft input gear which is supported by taper roller bearings.
Input gear bearing pre-load is achieved by the use of a selective shim located in the bearing housing.
Intermediate gears
The intermediate gear cluster is supported by the taper roller bearings located at each end of the cluster and runs on
the intermediate shaft which, in turn, is supported at the front and rear by the main casing.
A selective spacer, positioned between the gears, pre-loads the intermediate gear bearings when the intermediate
shaft nut is tightened sufficiently to achieve the correct 'torque to turn' of the intermediate gears.
On vehicles from 03 model year, the circlips used to retain the bearings in the intermediate gear are deleted. The bore
of the intermediate gear is machined with a shoulder at each end to locate the bearings.
Differential assembly
The differential assembly is supported at the front and rear by taper roller bearings, the front bearing outer track is
located in the front output housing and the rear bearing outer track is located in the main casing by the rear output
housing. Bearing pre-load is achieved by means of a selective shim located in the front output housing.
The differential rear shaft carries the low range gear, high/low selector sleeve and hub, high range gear and bush and
the differential rear bearing; these components being secured to the shaft by a special staked nut.
The differential assembly comprises front and rear half carriers with integral shafts and with sun and planet gears
mounted on cross shafts within the half carriers. Dished, non-selective thrust washers control the engagement of the
planet gears with the sun gears, whilst selective thrust washers are used to control engagement of the sun gears and
'torque to turn' of the differential. The differential carrier halves are bolted together, a retaining ring providing positive
location of the cross shafts.
The high/low selector shaft and fork are located at the side of the differential, movement of the shaft, fork and selector
sleeve being controlled by the high/low selector finger. A spring loaded detent ball fitted in the main casing, locates
in grooves in the shaft.
On vehicles from 03 model year, the selector fork is modified and fitted with a spring assistor and clips to reduce the
effort required to move the selector lever.
Front output housing
The front output housing carries the front output shaft and flange, high/low cross shaft, housing and selector and on
certain vehicles, the differential lock selector shaft and fork.
The front output shaft is supported in the housing by a single bearing and is splined into the differential front sun gear.
High/low selector
The high/low cross shaft is located in a housing bolted to the top of the output housing and is connected to the high/
low selector finger which locates in a slot in the selector shaft.

TRANSFER BOX - LT230SE
DESCRIPTION AND OPERATION 41-15
High/low detect switch
A high/low detect switch is fitted in the front output housing and connects to earth when low is selected. The switch is
connected to the engine ECM, the SLABS ECU and the EAT ECU. The purpose of the switch is to enable selection
of the hill descent feature and to modify the engine fuelling and automatic gearbox gearshift maps stored within the
respective ECM's and ECU's.
Differential lock - Fitted to certain vehicles only
The differential lock selector housing is bolted to the top of the front output housing, the selector finger passes through
the housing, locating in a slot in the differential lock selector shaft. The differential lock selector shaft passes through
the selector fork which is located beneath a plate bolted to the side of the output housing. The selector fork engages
the dog clutch sleeve with the differential rear shaft when the splines of the sleeve and differential rear shaft are
aligned. A spring loaded detent ball fitted in the output housing locates in grooves in the shaft.
Functionality – Vehicles up to 03 model year only
The function of the differential lock used in previous applications is performed on this vehicle by the Electronic Traction
Control System. However, for the purposes of 2 wheel rolling road testing , the differential lock components are
retained. For all driving conditions however, the differential lock must be set in the unlocked position.
Up to 03 model year specification shown
The differential lock must only be engaged for 2 wheel rolling road testing as engagement of the lock disables the
traction control feature and inhibits correct operation of the electronic brake distribution and hill descent features. 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. The lock may be engaged/disengaged by using a 10 mm open ended spanner
on the flats (arrowed) machined on the differential lock selector shaft.
Vehicles not fitted with a differential lock may be identified by there being no cover or selector shaft (arrowed) 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.

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
DESCRIPTION AND OPERATION 41-17
Lubrication
Lubrication is by splash, oil filler/level and drain plugs being located in the main casing.
Internal pressures caused by thermal expansion and contraction are avoided by the use of a plastic breather pipe
venting the interior of the box to atmosphere. The pipe is attached to the top of the high/low selector housing by a
banjo bolt and is then routed in a continuously rising path into the engine compartment where the open end is secured
by a clip attached to the engine cylinder block.
Oil temperature warning lamp switch
An oil temperature switch is fitted to V8 engine models. In the event of the transfer box oil approaching maximum
recommended working temperature of 145
°C (293°F), the switch will close and a warning lamp in the instrument pack
will be illuminated.
High/Low range and differential lock selector lever assembly – Vehicles from 03 model year
1Selector lever
2High/Low range cable
3Differential lock cable
4Interlock solenoid

TRANSFER BOX - LT230SE
ADJUSTMENTS 41-21
ADJUST ME NTS
Cable - high/low selector
$% 41.20.46
Adjust
1.Raise vehicle on ramp.
2.Using a suitable crows foot spanner, loosen
lock nuts securing outer cable to abutment
bracket.
3.Select high range by moving lever on transfer
gearbox fully forward.
4.Insert tool LRT-41-016 through hole in selector
lever and housing. This ensures selector
lever is in the high range position.
5.Lightly tighten outer cable lock nuts.
6.Remove tool LRT-41-016 from gear selector
lever and housing.
7.Simultaneously tighten high/low selector cable
lock nuts either side of abutment bracket to 30
Nm (22 lbf.ft) .
8.Lower vehicle on ramp.

TRANSFER BOX - LT230SE
REPAIRS 41-23
REPAIRS
Bottom cover - transfer box
$% 41.20.06
Remove
1.Raise vehicle on ramp.
2.Drain transfer box oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
3.Remove 8 bolts securing cross member to
chassis and remove cross member.
4.Remove 10 bolts securing bottom cover to
transfer box and remove cover. Refit
1.Clean bottom plate and mating face on transfer
box.
2.Clean bolt threads.
3.Apply sealant, Part No. STC 3254 to bottom
plate sealing face.
4.Apply Loctite 290 to bolt threads.
5.Position bottom plate and tighten bolts to 25
Nm (18 lbf.ft).
6.Position cross member to chassis and tighten
bolts to 26 Nm (19 lbf.ft).
7.Fill transfer box with oil.

+ MAINTENANCE, PROCEDURES,
Transfer box.
8.Lower vehicle on ramp.

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
REPAIRS 41-25
12. If fitted: Disconnect 2 Lucars from differential
lock switch and disconnect multiplug from
reverse light switch.
13.Remove cable tie and multi plug from bracket
on transfer box.
14.Release transfer box breather pipe from
bulkhead clip.
15.Remove 4 bolts from transfer box bottom plate,
position support plate LRT-99-010 to transfer
box and tighten bolts.
16.Position gearbox support jack and secure
support plate to jack using 4 bolts. 17.Remove 3 bolts securing transfer box to
gearbox.
18.Fit 3 guide studs LRT-41-009 through
transfer box bolt holes to support it during
removal.
19.Remove 2 bolts and nut securing transfer box
to gearbox. CAUTION: If securing stud is
removed during this operation, it must be
discarded and a new stud fitted.
20.Position a jack to support gearbox and engine.
21.Remove 4 bolts and nut, remove gearbox RH
mounting.
22.With assistance, remove transfer box from
gearbox.
23.Remove input shaft oil seal.

+ TRANSFER BOX - LT230SE,
REPAIRS, Oil seal - input shaft.