lock LAND ROVER DISCOVERY 2002 Workshop Manual

TRANSFER BOX - LT230SE
OVERHAUL 41-47
Inspect
1.Check mating surfaces of cross shaft and
housing bore for wear.
2.Check core plug in housing for signs of leakage
or corrosion ; apply Loctite 326 to replacement
plug.
3.Measuring across widest portion of finger,
check high/low selector finger for wear.
lFinger width = 15.90 to 15.95 mm (0.625 to
0.627 in).
4.Check bearing track recesses in housing for
damage, rectify or replace housing as
necessary.
5. If fitted: Carry out inspection of differential
lock components using following procedures.
6.Check differential lock selector shaft and
housing bore for wear.
7.Measuring across the widest portion, check
differential lock finger for wear.
lFinger width = 15.90 to 15.95 mm (0.625 to
0.627 in).8.Check differential lock selector finger groove in
selector shaft.
lGroove width = 16.0 to 16.1 mm (0.63 to
0.64 in).
9.Check detent grooves in differential lock
selector shaft for wear.
10.Check differential lock detent ball for flat spots
and check detent spring for distortion.

TRANSFER BOX - LT230SE
41-48 OVERHAUL
11.Check differential lock selector fork for cracks
and wear.
12.Check selector fork finger width.
lFinger width = 7.92 to 7.97 mm (0.311 to
0.313 in).
13.Check differential lock selector fork clips for
wear and damage. Check spring for distortion
and free length.
lSpring free length = 84.58 mm (3.33 in).
14.Check dog clutch internal teeth and grooves
and teeth on output shaft for wear and
damage. Check selector fork groove width.
lGroove width = 8.05 to 8.20 mm (0.32 to
0.33 in).
15.Carry out the following inspection procedures
for all transfer boxes.
16.Check threads and splines of output shaft for
damage and wear. Check dog clutch teeth on
shaft for wear and damage.17.03 MY onwards: Compress high/low selector
fork spring and remove retaining clips from
each end of spring, remove high/low selector
shaft.
18.Check detent grooves in high/low selector shaft
for wear. Do not remove fork from shaft
unless either component is being renewed.
If fork is removed from shaft, coat the
threads of the set screw with Loctite 290
prior to assembling.
Note: High/low selector shaft fitted to pre 03 MY
illustrated.

TRANSFER BOX - LT230SE
41-54 OVERHAUL
25.Position tool LRT-41-014/3 onto main casing.
26.Screw tool LRT-41-014/4 into tapped hole in
main casing and attach suitable DTI to pillar.
27.Position stylus of gauge to setting block LRT-
41-014/3 and zero gauge.
28.Position stylus onto front bearing outer track
and record reading. 29.Taking care not to disturb bearing, position
stylus on opposite side of bearing track and
record reading.
30.Obtain average of the 2 readings and record
figure.
31.Position depth block tool LRT-41-014/2 and
cross bar tool LRT-41-014/1 to front output
housing.
32.Position DTI to tool LRT-41-014/1 cross bar
and zero DTI on depth block.
33.Position DTI to cross bar and record reading
obtained.
34. Using the formula: 3.05 mm (0.120 in)+B-
A=D where: B=Height difference recorded
between depth block and cross bar.
A=Average of readings to differential front
bearing outer track. D=Thickness of shim
required to give differential bearing pre-load of
0.05 mm (0.002 in).
35.From the resultant figure obtained, select
appropriate thickness shim from the range
available.
36.Shims are available from 2.00 to 3.25 mm
(0.08 to 0.13 in) thickness, rising in increments
of 0.05 mm (0.002 in).

TRANSFER BOX - LT230SE
OVERHAUL 41-55
37.Heat the front output housing to 100°C (210°F)
and fit new output shaft bearing using tool
LRT-41-011.
38.Allow housing to air cool.
39.Fit new bearing retaining circlip ensuring that
circlip is fully seated.
40.Using tool LRT-41-012, fit new output shaft oil
seal. Check that oil seal is just contacting
circlip. 41.Position selected shim in front output housing
and using tool LRT-54-003, fit new differential
front bearing track.
42.Fit bearing spacer to output shaft with chamfer
on spacer towards threaded end.
43. If fitted: Fit dog clutch with flange on clutch
facing towards splined end.
44.Using a copper mallet, drive output shaft into
bearing.
Note: Carry out the following operations for
transfer boxes fitted with differential lock.
45.Compress differential lock selector spring and
fit selector fork.
46.Position selector fork to groove in dog clutch.
47.Fit selector shaft and locate in housing recess,
rotate shaft until the two flats for retaining clips
are at right angles to the cover plate mating
face.

TRANSFER BOX - LT230SE
41-56 OVERHAUL
48.Compress selector spring and fit retaining clips
at each end of spring.
CAUTION: Ensure ends of spring are fully
seated in recess of clips.
49.Fit detent ball and spring.
50.Apply Loctite 290 to threads of detent plug.
51.Fit and tighten detent plug, then loosen 2
complete turns.
52.Fit new 'O' ring to differential lock selector
housing.
53.Fit selector housing, ensure selector finger is
located in shaft recess.
54.Apply Loctite 290 to threads of bolts, and
tighten selector housing bolts to 25 Nm (18
lbf.ft).
55.Clean threads of differential lock warning lamp
switch(es).
56.Up to 03 MY: Fit nut to switch head with
counterbore positioned towards switch head.
The nut acts as a spacer to ensure that
switch setting is correct. Always ensure
that nut is fully tightened to switch head (no
gap).
57.Apply Hylomar PL 32 sealant to threads of
differential warning lamp switch(es).
58.Up to 03 MY: Position switch into front output
housing until nut bottoms out on housing;
tighten nut to 11 Nm (8 lbf.ft)
59.03 MY onwards: Fit new sealing washers to
switches, fit switches in front output housing
and tighten to 25Nm (18 lbf.ft).
Note: Carry out the following operations for all
transfer boxes.
60.Apply sealant, Part No. STC 3254 to front
output shaft housing. 61.Position housing ensuring that output shaft and
dog clutch splines - if fitted are correctly
engaged.
62.Clean output housing bolt threads.
63.Apply Loctite 290 to threads of bolts.
64.Fit output shaft housing bolts and tighten in a
diagonal sequence to 45 Nm (33 lbf.ft).
65.Fit output flange, new felt washer, steel washer
and new retaining nut.
66.Using tool LRT-51-003 to restrain flange,
tighten output flange nut to 162 Nm (119 lbf.ft).
67. If fitted - Operate differential lock selector
lever and check that detent ball can be felt to
positively engage/disengage with grooves in
shaft. Screw plug in or out until setting is
correct.
68.Fit high/low selector shaft detent ball and
spring.
69.Apply Loctite 290 sealant to threads of high/low
selector shaft detent plug.
70.Fit and tighten plug, then loosen 2 complete
turns.
71. Operate high/low selector lever and check that
detent ball can be felt to positively engage/
disengage with grooves in shaft. Screw plug in
or out until setting is correct.
72.Fit intermediate gear cluster.

+ TRANSFER BOX - LT230SE,
OVERHAUL, Intermediate gear assembly.

TRANSFER BOX - LT230SE
OVERHAUL 41-57
Dog clutch - differential lock
$% 41.20.23
Disassembly
1.Remove 6 bolts securing high/low cross shaft
housing to front output shaft housing and
remove housing.
2.Note position of longest bolt and remove 8
bolts securing front output shaft housing to
main casing and remove housing.
3.Remove 3 bolts securing differential lock
selector housing and remove housing. 4.Remove and discard 'O' ring from selector
housing.
5.Remove differential warning lamp switch and
locknut.
Note: Locknut is only fitted to switches up to 03
MY, a modified switch and sealing washer is
fitted from 03 MY onwards..
6.03 MY onwards: Remove differential lock
warning lamp switch from end of front output
shaft housing, discard sealing washer.
7.Remove Allen plug and remove detent spring
and ball.
8.Compress differential lock selector fork spring
and remove retaining clips from each end of
spring.
9.Withdraw differential lock selector shaft from
front output housing, recover spring and
remove selector fork.

TRANSFER BOX - LT230SE
41-58 OVERHAUL
10.Position tool LRT-51-003 to output shaft drive
flange, remove and discard nut.
11.Remove and discard steel and felt washers.
Remove output shaft drive flange.
12.Using a copper mallet, drive output shaft from
housing.
13.Noting its fitted position, remove bearing
spacer from output shaft.
14.Noting its fitted position, remove dog clutch
from output shaft.
15.Remove and discard oil seal from housing. Reassembly
1.Clean differential lock components.
2.Lubricate components with gearbox oil.
3.Using tool LRT-41-012, fit new output shaft oil
seal.
4.Fit bearing spacer to output shaft with chamfer
on spacer towards threaded end.
5.Fit dog clutch with flange on clutch facing
towards splined end.
6.Using a copper mallet, drive output shaft into
bearing.
7.Compress differential lock selector spring and
fit selector fork.
8.Position selector fork to groove in dog clutch.
9.Fit selector shaft and locate in housing recess,
rotate shaft until the two flats for retaining clips
are at right angles to the cover plate mating
face.
10.Compress selector spring and fit retaining clips
at each end of spring.
CAUTION: Ensure ends of spring are fully
seated in recess in clips.
11.Fit detent ball and spring.
12.Apply Loctite 290 to threads of detent plug.
13.Fit and tighten detent plug, then unscrew 2
complete turns.
14.Fit new 'O' ring to differential lock selector
housing.
15.Fit selector housing, ensure selector finger is
located in shaft recess.
16.Apply Loctite 290 to threads of bolts and tighten
selector housing bolts to 25 Nm (18 lbf.ft).
17.Apply sealant, Part No. STC 3254 to front
output shaft housing.
18.Position housing ensuring that output shaft and
dog clutch splines are correctly engaged.
19.Apply Loctite 290 to threads of bolts.
20.Fit front output shaft housing bolts and tighten
in a diagonal sequence to 45 Nm (33 lbf.ft).

TRANSFER BOX - LT230SE
OVERHAUL 41-59
21.Clean threads of differential lock warning lamp
switch(es).
22.Up to 03 MY: Fit nut to switch head with
counterbore positioned towards switch head.
The nut acts as a spacer to ensure that
switch setting is correct. Always ensure
that nut is fully tightened to switch head (no
gap).
23.Apply Hylomar PL 32 sealant to threads of
differential warning lamp switch(es).
24.Up to 03 MY: Position switch into front output
housing until nut bottoms out on housing,
tighten nut to 11 Nm (8 lbf.ft).
25.03 MY onwards: Fit new sealing washers to
switches, fir switches to front output housing
and tighten to 25 Nm (18 lbf.ft).
26.Operate differential lock selector lever and
check that detent ball can be felt to positively
engage/disengage with grooves in shaft.
Screw plug in or out until setting is correct.27.Fit output flange, new felt and steel washers
and new retaining nut.
28.Using tool LRT-51-003 to restrain flange,
tighten output flange nut to 162 Nm (119 lbf.ft).

TRANSFER BOX - LT230SE
41-62 OVERHAUL
7.Position dial gauge with stylus contacting input
gear, push input gear rearwards and zero
gauge.
8.Push input gear forwards and note gauge
reading.
9.Calculate thickness of shim required using the
formula - A+B+C=D where:
lA= Thickness of installed shim - 3.15 mm
(0.12 in)
lB= Recorded end-float.
lC= Required pre-load - 0.05 mm (0.002 in).
lD= Thickness of shim required.
10.If an alternative shim is required to establish
correct pre-load, fit an alternative shim. Shims
are available from 3.15 to 4.00 mm (0.12 to
0.16 in) thickness, in increments of 0.05 mm
(0.002 in).
11.Remove 2 bolts, remove bearing housing and
input gear.
12.Lubricate input gear and bearings with
recommended oil.
13.Position input gear into main casing.
14.Apply sealant, Part No. STC 3254 to bearing
housing and cover.
15.Position bearing housing/cover, align reference
marks and tighten by diagonal selection to 45
Nm (33 lbf.ft).
16.Using tool LRT-37-014 fit new input shaft oil
seal.
Low gear - differential
$% 41.20.62
Disassembly
1.Remove differential.

+ TRANSFER BOX - LT230SE,
OVERHAUL, Dog clutch - differential lock.
2.Secure differential in a soft jawed vice.
3.Release staking from bearing retaining nut.
4.Using tool LRT-41-007 remove and discard
bearing retaining nut.
5.Position tool LRT-99-002. to a vice.
6.Position tool LRT-41-001 around rear
differential bearing, position differential to tool
LRT-99-002 and press off bearing.

AUTOMATIC GEARBOX - ZF4HP22 - 24
44-4 DESCRIPTION AND OPERATION
Description
General
The automatic gearbox is a four speed unit with electronic control of gear selection, shift quality and torque converter
lock-up. Selections on the selector lever assembly are transmitted to the gearbox by a selector cable. A gear position
switch on the gearbox transmits the gear selection to an Electronic Automatic Transmission (EAT) ECU, which
outputs the appropriate control signals to an electro-hydraulic valve block in the gearbox. A mode switch enables the
driver to change the control mode of the EAT ECU. The EAT ECU operates warning lamps in the instrument pack to
indicate the control mode and system status.
The gearbox features a pressure lubrication system and is cooled by pumping the lubricant through an oil cooler.
On NAS market vehicles from 03 model year, the ZF 4HP24 transmission unit is introduced for use with the 4.6 litre
V8 engine. This transmission is required to accomodate the increased power output of the larger engine. The ZF
4HP22 transmission remains in use on vehicles with Td5 and 4.0 litre V8 engines.
Both transmission units are of similar construction, with the ZF 4HP24 unit being 15 mm longer than the 4HP22 unit
to accomodate a larger fluid pump. The operation of both transmission units is the same.
Selector lever assembly