LAND ROVER DISCOVERY 2002 Workshop Manual

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
OVERHAUL 41-49
19.Check width of high/low selector groove.
lGroove width = 16.0 to 16.1 mm (0.63 to
0.64 in).
20.Check high/low selector fork for cracks and
wear. Check selector fork finger width.
lFinger width = 7.37 to 7.47 mm (0.290 to
0.294 in).
21.03 MY onwards: Check high/low selector fork
clips for wear and damage. Check spring for
distortion, check free length of spring:
lSpring free length = 75 mm (2.95 in)
Note: High/low selector shaft, fork and spring
fitted to 03 MY transfer boxes may be fitted to
pre 03 MY boxes as an assembly.
22.Check differential sun and planet gears for
wear, cracks and chipping of teeth.
23.Check cross shafts and recesses in both halves
of differential carrier for damage and
wear.Ensure planet gears are retained with
their respective shafts.
24.Check retaining ring for distortion.
25.Check differential splines for wear and
damage.26.Check high/low hub for cracks, chipping and
uneven wear. Check width of selector fork
groove.
lGroove width = 7.5 to 7.6 mm (0.295 to 0.30
in).
27.Check splines and teeth on high/low selector
sleeve for uneven wear, cracks, damage and
chipping.
28.Check teeth of high and low range gears for
cracks, chipping and uneven wear.
29.Check high range gear bush for wear and
damage.
Reassembly
1.Lubricate all components with recommended
oil and lightly oil the differential bolt threads.

TRANSFER BOX - LT230SE
41-50 OVERHAUL
2.Secure rear half of differential carrier in a soft
jawed vice.
3.Fit each planet gear to its respective cross
shaft, fit new dished thrust washer to each
gear.
4.Fit cross shafts, planet gears and dished thrust
washers in rear half of carrier.Ensure that
cross shafts are fitted correctly. Do not fit
the sun gear into the rear half carrier at this
stage.
5.Fit retaining ring.
6.Fit a 1.05 mm (0.04 in) thrust washer to sun
gear from front half of carrier. Position gear in
front half of carrier.
7.Ensuring that assembly marks are aligned, fit
both halves of carrier together.
8.Fit the differential carrier bolts and, working in a
diagonal sequence, tighten the bolts to 60 Nm,
(44 lbf.ft).9.Insert the front output shaft into the front half of
the carrier and check that the gears rotate
freely.
10.Fit output flange on to the splines of the output
shaft, but do not fit flange nut at this stage.
11.Fit transmission brake drum to output flange
and secure the drum using 2 nuts.
12.Secure a length of cord around the drum and
attach one end of the cord to a spring balance.
13.Pull on the spring balance and note the load at
which the brake drum starts to turn. Used
gears should rotate smoothly, while new
gears will have a 'notchy' feel as they rotate.
14.Compare the figure obtained with the following.
lUsed gears = 0.45 kg (1.0 lb)
lNew gears = 1.72 kg (3.8 lb)
15.If the load to turn figure is below the specified
limits, proceed as follows.
16.Remove the front output shaft and brake drum.
17.Remove the 8 bolts securing the two halves of
the differential carrier
18.Separate the differential carrier and remove the
sun gear and thrust washer from the front half.
19.Select a thicker thrust washer from the range
available. 5 different thrust washers are
available, rising in increments of 0.10 mm
(0.004 in) from 1.05 mm to 1.45 mm (0.04 to
0.06 in).
20.Repeat steps 7 to 19 as necessary until the
load to turn figure is as specified
21.When specified load to turn is obtained,
proceed as follows.
22.Remove the front output shaft and brake drum.
23.Remove the 8 bolts securing the two halves of
the differential carrier
24.Separate the differential carrier and remove the
sun gear and thrust washer from the front
half.Retain the selected thrust washer with
its sun gear.

TRANSFER BOX - LT230SE
OVERHAUL 41-51
25.Remove retaining ring, then remove the planet
gears and cross shafts.
26.Fit a 1.05 mm (0.04 in) thrust washer to sun
gear from rear half of carrier. Position gear in
rear half of carrier.
27.Fit planet gears, cross shafts and dished thrust
washers to rear half of carrier. Ensure that
cross shafts are fitted correctly. Do not fit
the sun gear into the rear half carrier at this
stage.
28.Fit retaining ring.
29.Ensuring that assembly marks are aligned, fit
both halves of carrier together.
30.Fit the differential carrier bolts and, working in a
diagonal sequence, tighten the bolts to 60 Nm,
(44 lbf.ft).31.Invert the assembly in the vice, insert the rear
output shaft into the rear half of the carrier and
check that the gears rotate freely.
32.Fit output flange on to the splines of the output
shaft, but do not fit flange nut at this stage.
33.Fit transmission brake drum to output flange
and secure the drum using 2 nuts.
34.Carry out the load to turn check, using the same
method as for the front half carrier. Record the
shim thickness when the load to turn is correct.
35.Fit the sun gear and selected thickness shim to
the front half carrier.
36.Ensuring that assembly marks are aligned, fit
both halves of carrier together.
37.Fit the differential carrier bolts and, working in a
diagonal sequence, tighten the bolts to 60 Nm,
(44 lbf.ft).
38.With differential assembled, fit rear output shaft
and brake drum, then check overall load to turn.
This should be approximately the same as the
combined load to turn figure of both front and
rear half carriers.
lUsed gears = 0.90 kg (2.0 lb)
lNew gears = 3.44 kg (7.6 lb)

TRANSFER BOX - LT230SE
41-52 OVERHAUL
Refit
1.Clean differential components.
2.Lubricate components with gearbox oil.
3.Position differential in soft jawed vice and fit
front bearing using tool LRT-41-008.
4.Invert differential in soft jawed vice, and fit low
range gear with dog teeth facing uppermost. 5.Fit high/low hub ensuring that machined
groove on hub teeth faces towards low range
gear.
6.Fit high/low selector sleeve ensuring that
alignment marks on hub and sleeve are
together.
7.Fit bush to high range gear ensuring collar is
uppermost.
8.Fit high range gear and bush onto shaft.
9.Fit new rear bearing using tool LRT-41-008.
10.Using tool LRT-41-007, fit new bearing
retaining nut and tighten to 72 Nm (53 lbf.ft).
Do not stake nut at this stage.

TRANSFER BOX - LT230SE
OVERHAUL 41-53
11.Using feeler gauges, determine clearance
between low range gear and high/low hub:
lClearance = 0.05 to 0.15 mm (0.002 to
0.006 in).
12.If clearance is not as specified, fit a new low
range gear and high/low hub and re-check.
13.Using feeler gauges, determine clearance
between high range gear and high/low hub:
lClearance = 0.05 to 0.15 mm (0.002 to
0.006 in).
14.If clearance is not as specified, fit new high
range gear and high/low hub and re-check. 15.Using a suitable drift, stake collar of nut into
differential shaft recess.
16.Using LRT-51-009, fit new rear bearing track
into main casing.
17.Using a straight edge and feeler gauges, check
that bearing track is recessed 1 mm (0.04 in)
below outer face of main casing.
18.Apply sealant, Part No. STC 3254 to rear
output shaft housing face.
19.Position housing to main casing.
20.Apply Loctite 290 to bolt threads fit housing to
main case bolts and tighten by diagonal
selection to 45 Nm (33 lbf.ft).
21.03 MY only: Fit high/low selector fork and
spring to high/low selector shaft, fit retaining
clips.
CAUTION: Ensure ends of spring are fully
seated in recess in clips.
22.Position high/low selector shaft and fork to
differential ensuring that fingers of selector fork
are located in selector sleeve.
23.Position differential assembly into main casing
ensuring that splines of rear output shaft are
engaged in differential.
24.Position new differential front bearing track
ensuring that track is seated squarely.

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.