oil level LAND ROVER DISCOVERY 1999 Owner's Manual

MANUAL GEARBOX - R380
DESCRIPTION AND OPERATION 37-7
Description
General
The R380 all synchromesh gearbox has five forward speeds and reverse and is mounted in line with the engine. The
clutch bell housing is bolted to the front of the gearbox and the transfer box is mounted at the rear.
Gearbox casings
Gearbox casings consist of a front cover, gearcase, centre plate and extension housing. All casings with the exception
of the front cover are located to each other by dowels and sealed. Gearbox filler/level and drain plugs are located in
the gearcase.
Reverse lamp switch
A reverse lamp switch is inserted into the extension housing. Selection of reverse gear will close the switch allowing
current from fuse 25 to flow through the switch to illuminate the reverse lamps. The switch also provides a feed to the
BCU and the electrochromic automatic interior mirror - if fitted; the mirror moving from the dimmed position if
applicable.
Gearchange assembly
The gearchange assembly is bolted to the top of the gearcase, the upper gear lever being attached to the lower gear
lever by means of a clamp bolt. The lower gear lever ball is housed in a Railko bush inserted in the gear change
housing, the end of the lever locating in the selector yoke which is attached to the end of the selector shaft. Bias
springs provide a positive return of the gear lever to the neutral position with selection of 1st/2nd and 5th/reverse gears
being against bias spring pressure. Spring loaded detent balls fitted in the centre plate locate in grooves in the selector
shaft to provide positive gear and neutral selection.
Lubrication
Lubrication is by an oil pump located in the extension housing and driven by the layshaft with additional lubrication
being provided by splash. The pump directs oil via a filter and internal drillings in the output shaft to lubricate the
components. On non UK and non European models, provision for oil cooling is by means of a thermostat housed in
a cover bolted to the side of the extension housing. The cover incorporates tappings for connections to an oil cooler.
On UK and European models, the thermostat and cover are replaced by an oil by-pass block.
Internal pressures produced within the gearbox are vented to atmosphere via a plastic breather pipe. The pipe is
attached to the extension housing and is routed across the top of the gearcase and secured at the open end by a clip
attached to the engine cylinder block.
Selector shaft and forks
Selector forks for 1st/2nd, 3rd/4th and 5th/reverse gears are located on a single selector shaft; the 1st/2nd and 3rd/
4th selector forks are inside the main gearcase whilst the 5th/reverse selector fork is inside the extension housing.
Each of the selector forks locates inside its corresponding synchromesh hub.
Synchromesh assemblies
Each synchromesh assembly is located on the output shaft adjacent to its corresponding gears and comprises a
synchromesh ring, hub, slippers and sleeve. The hubs and slippers are retained in the sleeves by means of spring
clips. 1st/2nd and 3rd synchromesh assemblies are fitted with double synchromesh rings whilst 4th, 5th and reverse
assemblies are fitted with single rings.
The gear train
The gear train comprises an input shaft, output shaft, layshaft and reverse idler shaft together with their appropriate
gears and synchromesh assemblies.
The gear train input shaft, output shaft and layshaft are supported by taper roller bearings with all gears on the input
and output shafts running on caged needle roller bearings. Layshaft gears are integral with the shaft with the
exception of reverse/5th gears which are splined to the shaft and retained with a nut. 1st, 2nd, 3rd and 4th gears are
shot peened to improve durability. The reverse idler shaft and gear are supported in the centre plate by a caged
needle roller bearing. End-float of the output shaft and layshaft is controlled by selective shims located in the centre
plate whilst reverse idler shaft end-float is controlled by a selective shim located behind reverse gear.

MANUAL GEARBOX - R380
REPAIRS 37-23
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.
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.

TRANSFER BOX - LT230SE
41-4 DESCRIPTION AND OPERATION
Main casing components – Vehicles up
to 03 model year
1Retaining plate
2Stake nut - intermediate shaft
3Bolt - retaining plate
4'O' rings - intermediate shaft
5Bearings and outer tracks - mainshaft input
gear
6Mainshaft input gear bearing housing
7Cover plate
8Bolt - cover plate
9Selective shim
10Mainshaft input gear
11Oil filler/level plug
12Oil temperature switch - if fitted
13Bearings and outer tracks - intermediate gears
14Circlips
15Intermediate gears
16Bottom cover plate
17Bolt - bottom cover plate
18Selective spacer19Mainshaft oil seal
20Oil drain plug
21Main casing
22Intermediate shaft
23Locating dowel
24Detent ball - high/low selector
25Detent spring - high/low selector
26Detent plug - high/low selector
27Neutral warning switch - Automatic gearbox
only - North America and Japan
28Bolt - interlock solenoid cover - Automatic
gearbox only - North America and Japan
29Cover - interlock solenoid - Automatic gearbox
only - North America and Japan
30Belleville washer - Automatic gearbox only -
North America and Japan
31Interlock solenoid - Automatic gearbox only -
North America and Japan

TRANSFER BOX - LT230SE
DESCRIPTION AND OPERATION 41-5
Main casing components – Vehicles
from 03 model year
1Retaining plate
2Stake nut - intermediate shaft
3Bolt - retaining plate
4'O' rings - intermediate shaft
5Bearings and outer tracks - mainshaft input
gear
6Mainshaft input gear bearing housing
7Cover plate
8Bolt - cover plate
9Selective shim
10Mainshaft input gear
11Oil filler/level plug
12Bearings and outer tracks - intermediate gears
13Intermediate gears14Bottom cover plate
15Bolt - bottom cover plate
16Selective spacer
17Mainshaft oil seal
18Oil drain plug
19Main casing
20Intermediate shaft
21Locating dowel
22Detent ball - high/low selector
23Detent spring - high/low selector
24Detent plug - high/low selector
25Neutral warning switch - Automatic gearbox
only - North America and Japan

TRANSFER BOX - LT230SE
41-16 DESCRIPTION AND OPERATION
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 - Vehicles from 03 model year
Vehicles from 03 model year are fitted with two differential lock warning lamp switches.
Both switches are of a new design and are fitted into the top of the front output housing. The switches are connected
to the SLABS ECU and are 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
The differential lock warning lamp is amber coloured and is located in the instrument pack.
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.
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 up to 03 Model Year. 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.

REAR AXLE
DESCRIPTION AND OPERATION 51-1
REAR AXLE DESCRIPTION AND OPERAT ION
Rear axle component layout
1Drive shaft
2'O' ring
3Hub bearing
4Stake nut
5Hub flange
6Breather tube
7Bolt
8Bolt
9Oil seal10Pinion flange
11Centralising peg
12Bolt
13Washer
14Differential unit
15Drain plug
16Axle casing
17Oil level plug
18'O' ring

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
51-8 REPAIRS
Refit
1.Clean pinion oil seal recess and pinion flange.
2.Lubricate oil seal lip with clean differential oil.

+ CAPACITIES, FLUIDS,
LUBRICANTS AND SEALANTS,
Lubrication.
3.Using tool LRT-51-010, fit pinion oil seal.
4.Fit pinion flange and securing bolt and washer.
Using tool LRT-51-003 to restrain pinion
flange, tighten pinion flange securing bolt to
100 Nm (74 lbf.ft).
5.Using a tubular drift, fit centralising peg to
pinion flange. Ensure that large diameter part of
centralising peg is below pinion flange
mounting surface.
6.Position propeller shaft and align reference
marks.
7.Fit nuts and bolts securing flexible coupling to
pinion flange and tighten to 76 Nm (55 lbf.ft).
8.Remove stand(s) and lower vehicle.
9.Check differential oil level.

+ MAINTENANCE, PROCEDURES,
Front and rear axle.
M51 0047A
LRT-51-003

FRONT AXLE
DESCRIPTION AND OPERATION 54-1
FRONT AXLE DESCRIPTION AND OPERAT ION
Front axle component layout
1Stake nut
2Hub flange
3Hub bearing
4Steering knuckle
5Drive shaft
6Oil seal
7Bolt
8Bolt
9Washer10Drive flange
11Oil seal
12Differential unit
13Drain plug
14Axle casing
15Breather tube
16Oil level plug
17'O' ring

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.