LAND ROVER DISCOVERY 1999 Workshop Manual

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.

TRANSFER BOX - LT230SE
DESCRIPTION AND OPERATION 41-17
High/Low range and differential lock selector lever assembly – Vehicles from 03 model year
1Selector lever
2High/Low range cable
3Differential lock cable4Interlock solenoid - North America and Japan
only
On vehicles fitted with a differential lock, the high/low range selector lever as fitted on previous models also
incorporates the differential lock selector on vehicles from 03 model year.
The lever can be moved forwards or backwards to select high, neutral or low range or sideways to select differential
lock engaged or disengaged, on vehicles with differential lock fitted.
The selector lever assembly comprises an aluminium casting with bosses for location of the two cables, the selector
lever mechanism and a housing for the interlock solenoid (if fitted). The upper face of the casting has threaded holes
which allow for the attachment of the casting to the mounting plate which is attached to the transmission tunnel.
A boss at the front provides location for the differential lock cable. The cable is attached to a lever which in turn is
attached to the selector lever. Movement of the selector lever is passed via the lever to the cable which moves the
differential lock selector shaft.
A second boss provides for the location of the high/low range cable. The cable is attached to a plate which moves in
a forward or rearward direction with the selector lever. On North American and Japanese specification models, plate
movement is prevented by an interlock solenoid when the ignition key is not in the ignition.
When fitted, the interlock solenoid is located on the right hand side of the selector lever casting. The solenoid is fitted
into a cast housing in the casting and retained with a circlip. Sealant is applied over the circlip to seal the solenoid in
the housing to prevent the ingress of dirt and moisture. The solenoid performs the same function as on previous
models, preventing the selection of neutral on the transfer box when the ignition key is not in the ignition.
A setting procedure is required for both the differential lock cable and the high/low range cable.

TRANSFER BOX - LT230SE
41-18 DESCRIPTION AND OPERATION
Operation
Power flow - transfer box in LOW ratio
Up to 03 Model Year section shown. from 03 Model Year similar

TRANSFER BOX - LT230SE
DESCRIPTION AND OPERATION 41-19
Power flow - transfer box in HIGH ratio
Up to 03 Model Year section shown, from 03MY similar
The gearbox output shaft transmits power to the mainshaft input gear which is in constant mesh with one of the
intermediate gears. The intermediate gears are in constant mesh with the high and low range output gears running
on the differential rear shaft.
Power is transmitted to the output shafts via the differential assembly by locking either the high or low range gears to
the differential rear shaft. This is achieved by means of the high/low selector fork, sleeve and splined hub.

TRANSFER BOX - LT230SE
ADJUSTMENTS 41-21
ADJUST ME NTS
Cable - selector - differential lock - adjust
$% 41.20.11
Check
1.Check operation of differential lock selection
and adjust cable if required.
Adjust
1.Remove front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
2.Loosen locknuts securing outer cable to
abutment bracket.
3.Move differential lock selector lever to non
differential lock position.
4.Move differential lever on transfer gearbox fully
forward to rotate selector shaft anti-clockwise
into the non differential lock detent position.
CAUTION: Should the lever move past the
detent, allow it to move back into the non
differential lock detent position before
adjusting the cable.
5.Without moving levers, simultaneously tighten
differential lock outer cable locknuts either side
of the abutment bracket to 30 Nm (22 lbf.ft).
6.Fit front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
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.Check that tool LRT-41-016 is a sliding fit in
selector lever and housing.
6.Simultaneously tighten high/low selector cable
lock nuts either side of abutment bracket to 30
Nm (22 lbf.ft) .
7.Remove tool LRT-41-016 from gear selector
lever and housing.
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 4600 to bottom
plate sealing face.
4.Apply sealant, Part No. STC 50552 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
Cable - selector - differential lock
$% 41.20.12
Remove
1.Remove centre console.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - automatic
models.
2.Remove 4 bolts securing transfer gearbox high/
low selector lever to transmission tunnel.
3.Remove front propeller shaft.

+ PROPELLER SHAFTS, REPAIRS,
Propeller shaft - front.
4. Models fitted with high/low shift interlock
solenoid: Release interlock solenoid multiplug
and disconnect multiplug from main harness.
5. Models fitted with high/low shift interlock
solenoid: Remove sleeve retaining rings and
remove sleeve from high/low select cable.
6.Release and remove clevis pin and 'C' clip
securing transfer gearbox high/low selector
cable to transfer gearbox high/low selector
lever. Position the cable aside.7.Release and remove clevis pin securing
differential lock selector cable to transfer
gearbox.
8.Loosen locknuts securing differential lock
selector cable to differential lock selector cable
abutment bracket.
9.Release and remove differential lock selector
cable from differential lock selector cable
abutment bracket.
10.Remove transfer gearbox high/low selector
lever assembly from transmission tunnel.
11.Release and remove clevis pin and 'C' clip
securing differential lock selector cable to
differential lock selector lever. Remove the
differential lock selector cable.

TRANSFER BOX - LT230SE
REPAIRS 41-25
Refit
1.Fit differential lock selector cable to differential
lock selector lever and secure with clevis pin
and 'C' clip.
2.Position transfer gearbox high/low selector
lever assembly to transmission tunnel.
3.Position differential lock selector cable to
differential lock selector cable abutment
bracket and tighten locknuts sufficiently to
retain cable.
4.Fit differential lock selector cable to transfer
gearbox and secure with clevis pin.
5.Fit transfer gearbox high/low selector cable to
transfer gearbox high/low selector lever and
secure with clevis pin and 'C' clip.
6.Fit transfer gearbox high/low selector lever to
transmission tunnel, fit bolts and tighten to 10
Nm (7 lbf.ft).
7. Models fitted with high/low shift interlock
solenoid: Position interlock solenoid harness
to high/low shift cable, fit sleeve around cable
and harness and secure sleeve.
8. Models fitted with high/low shift interlock
solenoid: Connect solenoid multiplug to main
harness and secure multiplug to bracket.
9.Check and adjust differential lock selector
cable.

+ TRANSFER BOX - LT230SE,
ADJUSTMENTS, Cable - selector -
differential lock - adjust.
10.Fit centre console.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - automatic
models.
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.