2002 LAND ROVER DISCOVERY ABS

CLUTCH - V8
33-2-6 DESCRIPTION AND OPERATION
Description
General
The clutch system is a conventional diaphragm type clutch operated by a hydraulic cylinder. The clutch requires no
adjustment to compensate for wear.
Hydraulic clutch
The hydraulic clutch comprises a master cylinder, slave cylinder and a hydraulic reservoir, which is also shared with
the braking system. The master and slave cylinders are connected to each other hydraulically by plastic and metal
pipes. The plastic section of the pipe allows ease of pipe routing and also absorbs engine movements and vibrations.
The master cylinder comprises a body with a central bore. Two ports in the body connect the bore to the hydraulic
feed pipe to the slave cylinder and the brake/clutch fluid reservoir. A piston is fitted in the bore and has an external
rod which is attached to the clutch pedal with a pin. Two coiled springs on the clutch pedal reduce the effort required
to depress the pedal.
The master cylinder is mounted on the bulkhead in the engine compartment and secured with two bolts. The cylinder
is connected to the shared brake/clutch reservoir on the brake servo by a braided connecting hose.
The slave cylinder is located on the left hand side of the gearbox housing and secured with two bolts. A heat shield
protects the underside of the cylinder from heat generated from the exhaust system. The slave cylinder comprises a
cylinder with a piston and a rod. A port in the cylinder body provides the attachment for the hydraulic feed pipe from
the master cylinder. A second port is fitted with a bleed nipple for removing air from the hydraulic system after
servicing. The piston rod locates on a clutch release lever located in the gearbox housing. The rod is positively
retained on the release lever with a clip.
Clutch mechanism
The clutch mechanism comprises a flywheel, drive plate, pressure plate, release lever and a release bearing. The
clutch mechanism is fully enclosed at the rear of the engine by the gearbox housing.
A clutch release bearing sleeve is attached in the gearbox housing with two bolts and located on two dowels. A spigot
with a ball end is formed on the release bearing sleeve and provides a mounting and pivot point for the clutch release
lever. A dished pivot washer is located on the ball of the spigot. When the release lever is located on the ball, the pivot
washer seats against the rear face of the release lever. A spring clip is located on the lever and the pivot washer and
secures the lever on the spigot. A small bolt retains the spring clip in position.
The release lever is forked at its inner end and locates on the clutch release bearing carrier. The outer end of the
release lever has a nylon seat which locates the slave cylinder piston rod. A second nylon seat, positioned centrally
on the release lever, locates on the ball spigot of the release bearing sleeve and allows the release lever to pivot freely
around the ball.
The clutch release bearing locates on the clutch release lever and the release bearing sleeve. The bearing is retained
on a carrier which has two flats to prevent the carrier rotating on the release lever. A clip retains the release lever on
the carrier. The bearing and carrier are not serviceable individually.

MANUAL GEARBOX - R380
37-22 REPAIRS
Refit
1.Using a suitable solvent 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.
6.Position seal housing, fit new bolts and tighten
by diagonal selection to 25 Nm (18 lbf.ft).
7.Clean bell housing mating faces, dowels and
dowel holes.
8.Position bell housing, fit bolts and tighten to 75
Nm (55 lbf.ft).
9.Clean release bearing sleeve mating faces,
dowel and dowel holes.
10.Position release bearing sleeve, fit bolts and
tighten to 25 Nm (18 lbf.ft).
11.Examine clutch release fork pivot points for
wear and replace as required.
12.Apply a smear of Molybdenum disulphide
grease to pivot points and position release
fork.
13.Fit retaining clip ensuring it locates over pivot
point washer, fit release fork bolt and tighten to
10 Nm (7 lbf.ft).
14.Clean release bearing and bearing sleeve
mating faces.
15.Apply smear of Molybdenum disulphide grease
to release bearing sleeve.
16.Fit release bearing and secure with retaining
peg.
17.Fit gearbox assembly.

+ MANUAL GEARBOX - R380,
REPAIRS, Gearbox - V8.
Cooler - oil - gearbox - Diesel
$% 37.24.02
Remove
1.Remove intercooler.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Intercooler.
2.Position absorbent cloth under each gearbox
oil cooler hose connection to collect spillage.
3.Push against coupling release ring and
disconnect both fluid hoses from oil cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
4.Remove screw securing oil cooler to radiator.

MANUAL GEARBOX - R380
REPAIRS 37-23
5.Release oil cooler from location on radiator,
and remove the oil cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
Refit
1.Fit oil cooler to radiator and secure with screw.
2.Ensure connections are clean and secure
hoses to cooler.
3.Fit intercooler.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Intercooler.
4.Top up gearbox oil level.

+ MAINTENANCE, PROCEDURES,
Manual gearbox.
Cooler - oil - gearbox - V8
$% 37.24.02
Remove
1. If fitted: Remove engine oil cooler.

+ ENGINE - V8, REPAIRS, Cooler -
engine oil.
2.Position absorbent cloth under each gearbox
oil cooler hose connection to collect spillage.
3.Push against coupling release rings and
disconnect both hoses from oil cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
4.Remove screw securing oil cooler to radiator.
5.Release oil cooler from its location on radiator.

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.

AUTOMATIC GEARBOX - ZF4HP22 - 24
44-12 DESCRIPTION AND OPERATION
Reverse gear
Clutches (5), (8) and (11) are engaged. The front planet gear carrier of gear set (9) is locked. Gear set (10) also rotates
as a solid block.
Gear position switch
The gear position switch outputs signals that are related to the position of the selector lever assembly. The switch is
installed on the selector shaft on the left side of the gearbox. Slotted mounting holes allow the switch to be turned
relative to the shaft for adjustment. A fly lead connects the switch to the vehicle wiring.
Movement of the selector lever assembly turns the selector shaft, which operates six pairs of contacts in the switch.
The pairs of contacts are identified as the W, X, Y, Z, Park/Neutral and Reverse contacts. When closed:
lThe W, X, Y and Z contacts output a 12V ignition supply from the BCU.
lThe Park/Neutral contacts output an earth.
lThe Reverse contacts output a 12V ignition supply from the passenger compartment fuse box.
The outputs of the W, X, Y and Z contacts are monitored by the EAT ECU and the BCU to determine the position of
the selector lever assembly.
Gear position switch W, X, Y, Z outputs
The Park/Neutral contacts output to the BCU and, on diesel models, the ECM. The Reverse contacts output to the
BCU, the reversing lamps, the SLABS ECU and, where fitted, the ACE ECU and the electrochromic interior mirror.
Switch
contactsOutput
PRND 3 2 1
W12V - 12V 12V - - -
X- 12V 12V - 12V - -
Y- - 12V 12V 12V - 12V
Z- - - 12V 12V 12V -

AUTOMATIC GEARBOX - ZF4HP22 - 24
REPAIRS 44-45
Filter - oil
$% 44.24.07
Remove
1.Remove oil sump gasket.

+ AUTOMATIC GEARBOX - ZF4HP22
- 24, REPAIRS, Gasket - oil sump.
2.Remove Torx screw securing oil pick-up tube
and remove tube.
3.Remove 2 Torx screws securing filter to valve
body and discard 'O' rings.
Refit
1.Clean filter and pick-up tube using a lint free
cloth.
2.Fit new 'O' rings to filter.
3.Position filter and tighten Torx screws to 8 Nm
(6 lbf.ft).
4.Position oil pick-up tube and tighten Torx
screw to 8 Nm (6 lbf.ft).
5.Fit oil sump gasket.

+ AUTOMATIC GEARBOX - ZF4HP22
- 24, REPAIRS, Gasket - oil sump.
Cooler - fluid - Td5
$% 44.24.10
Remove
1.Remove intercooler.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Intercooler.
2.Disconnect fluid temperature sensor multiplug.
3.Position absorbent cloth under each gearbox
cooler hose connection to collect spillage.
4.Push against coupling release ring and
disconnect both fluid hoses from cooler.
5.Remove screw and release cooler from
radiator.
6.Carefully remove cooler.

AUTOMATIC GEARBOX - ZF4HP22 - 24
44-46 REPAIRS
7.Remove temperature sensor and discard
sealing washer.
Refit
1.Use new sealing washer and tighten
temperature sensor to 14 Nm (10 lbf.ft).
2.Fit cooler, engage with radiator and secure with
screw.
3.Connect temperature sensor multiplug.
4.Ensure connections are clean and fit hoses to
cooler.
5.Fit intercooler.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Intercooler.
6.Check and if necessary top up gearbox fluid.
Cooler - fluid - V8
$% 44.24.10
Remove
1. If fitted: Remove engine oil cooler.

+ ENGINE - V8, REPAIRS, Cooler -
engine oil.
2.Disconnect fluid temperature sensor multiplug.
3.Position absorbent cloth under each gearbox
cooler hose connection to collect spillage.
4.Push against coupling release ring and
disconnect both fluid hoses from cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
5.Remove screw and release cooler from
radiator.
6.Carefully move radiator towards engine and
remove cooler.