Content .. 66 67 68 69 ..

Defender 90 / 110 / 130. Manual - part 68

LT77

FIVE SPEED

GEARBOX

REMOVE LT77

FIVE SPEED GEARBOX AND 230R

TRANSFER

BOX

FOUR CYLINDER MODELS

1. Install the vehicle

a ramp.

2. Disconnect the battery.
3 . Remove the gear lever knob.

4. Remove the transfer and differential lock knob.

5 .

Remove the gear lever cover.

6. Remove t h e 10

Nyloc nut and plain washer.

Mark the gear lever spline setting and

the

gear lever and gaiter from the splined lower gear
lever.

7. Select high range to prevent the transfer gearbox

selector lever fouling t h e tunnel when removing the
gearbox.

Remove the bonnet.

9. Remove the nuts and bolts retaining the fan cowl to

the engine and move the cowling forward, clear of

10. Release

the

transmission

breather

pipes,

speedometer cable, and starter motor harness from
clips at rear of the engine.

11. Release clamp holding heater pipes

on top of

engine to prevent heater inlet pipe fouling
bulkhead.

the engine.

12. Raise the ramp.
13. Remove the eight nuts and bolts securing the

chassis cross member and using a suitable means of
spreading t h e chassis, remove the cross member.

14.

Place

a suitable container under the transmission,

remove the three drain plugs, allow the oil

to drain

and refit

plugs. Clean filter on

extension

housing plug before refitting.

15. Remove

t h e

intermediate exhaust pipe and silencer

section

as follows:

(a)

(b)

(c)

Release the connection to the front pipe at
the flange.

Release t h e connection to the rear section at
the flange immediately behind the silencer.
Remove the

'U' bolt retaining the pipe to the

bracket attached to the transfer box.

16. Mark the flanges for reassembly and disconnect the

front propeller shaft from the transfer box.

17. Similarly, disconnect the

rear

propeller shaft.

18. Disconnect the speedometer cable from

rear of

the transfer box.
Disconnect the handbrake inner cable by removing
the split pin and clevis pin.

20. Slacken t h e retaining nuts and release the

handbrake outer cable from t h e bracket.

21.

Remove

t h e

two

bolts and withdraw the clutch

slave cylinder from the bell housing.

22. Manufacture

a cradle to the dimensions given in

the drawing and attach

i t

to a transmission hoist.

To achieve balance of the transmission

unit

when

mounted on the transmission hoist, it is essential
that point

is situated

the centre of the lifting

hoist ram. Drill fixing holes

B to suit hoist table.

Secure the transmission unit to

lifting bracket

at point C, by means of the lower bolts retaining
the transfer gearbox rear cover.

23. Remove the bottom two bolts from the transfer

box rear cover and use them to attach

rear end

t h e

cradle to the transfer box. Ensure that the

tube

in the centre of the cradle locates over the

extension housing drain plug.

24.

Raise the hoist just enough to take the weight of

the

transmission.

5.0

6.0

A N C

5.0

6.0

222.0

( P a r t

5135

FIVE

SPEED GEARBOX

25. Remove the three nuts and bolts securing the transfer

box L.H. and R.H. mounting brackets

the chassis.

26. Remove

the nuts retaining

the brackets to t h e

mounting rubbers and remove

brackets.

27. Lower the hoist sufficiently to allow the transfer

lever to clear the transmission tunnel aperture.

28. Disconnect t h e four-wheel drive indicator electrical

lead (bullet connection).

29. Remove the cleat retaining the reverse light switch

wires from the

R.H. side of

gearbox.

30. Disconnect

t h e

wire from the reverse light switch

situated at the top rear of the selector housing and
rnove the harness away from the transmission.

31. Support the engine under the sump with a jack,

placing timber between the jack pad and sump.

32. Remove the eleven hell housing nuts.
33. Withdraw the transmission whilst ensuring all

connections to the engine and chassis are released.

Separating the transfer box from gearbox

41. Withdraw the transfer box.

For

transfer

gear box dismantling refer to page 19. Dismantling
information on

gearbox, refer to page

Assembling transfer box to main gearbox

42. Hoist the transfer box into position and ensuring

that the loose upper dowel is fitted, assemble to
main gearbox extension housing and secure with
the four bolts and two nuts.

43.

Fit the transfer selector housing to the main

gearbox remote gear change housing

with

t h e

four

bolts. (The right hand rear bolt is longer).

44.

Fit the breather pipes.

45.

Fit the diffcrential lock cross shaft lever pivot
bracket to the extension housing

with

two

bolts.

46. Connect the cranked lever to the differential lock

lever with a new split pin.

(On early production

connect the short link with a new ‘Nyloc’ nut).

Fitting main gearbox and transfer box to engine

47. Fit the cradle to the transmission hoist and the

transmission to the cradle as described

instruction 23. Smear Hylomar

on bell housing face

mating with engine.

48. Locatc the gear

temporarily and select any

gear

the main gearbox

t o

entry

of the

primary shaft.

49. Position and raise hoist and

fit

t h e

transmission to

the engine whilst keeping wires and pipes clear to

prevent trapping.

50. Secure the transmission to the engine with the

eleven nuts, noting that the

top R . H . nut holds a

clip for the speedometer cable.

51. Position the

light wires to the

R.1-I. side of

the main gearbox and secure with a cleat to the
breather pipes.

top

of the selcctor housing.

53.

the differential lock indicator wires (bullet

connection).

54. Raise

transmission to line-up with the engine

and ensure that

t h e

transfer lever clears the tunnel

aperture.
Fit

the transfer box L.H. and R . H . mounting

brackets but only partially tighten the securing nuts
and bolts.

56. Loosely fit the rubber mounting nuts and lower the

transmission

onto t h e mountings. Fully tighten all

the securing nuts and bolts.

57. Remove the supporting jack from under the engine

58.

Remove the two bolts securing the cradle to the
transfer box and remove the cradle and hoist.

59. Refit

two bolts using Loctite

290 o n the threads

and note that t h e L.H. bolt holds a clip for the

speedometer cable.

60. Fit the slave cylinder using Hylosil on the gasket

and tighten

two bolts evenly to 22 to 28

(16

to 21

ft).

52. Connect the reverse light wire to the switch at the

LT77 FIVE

SPEED GEARBOX

61.

Fit the handbrake cable using a new split pin to

secure the clevis pin. Grease the clevis and tighten
the outer cable lock nuts.

62. Connect the speedometer cable.
63. Check that

t h e

three drain plugs are tight and

remove the main gearbox and transfer box filler
level

plugs.

Fill

the main

gcarbox

with

approximately

litres

pints)

recommended

oil

or until

begins to run out of the

filler  level  hole.  Fit  and  tighten  the  filler  plug.
Similarly  remove  t h e   transfer  filler  level  plug  and
inject  approximately

litres (4.5 pints) of

recommended oil

or until it runs out

the filler

hole. Apply Hylosil

to the threads and fit the plug

and wipe away any surplus

oil.

64. Line up the marks and fit the front and rear

propeller shafts to the transfer box.

65.

Fit the exhaust system, and evenly tighten the

flange nuts and bolts.

Fit the ‘U’ bolt and secure to

the bracket.

66. Expand the chassis side members, fit the cross

member and secure with the eight n u t s and bolts
(four each side).

67.

Fit t h e heater pipe clamp.

68. Clip the breather pipes, specdometer cable and

69. Fit

fan cowl.

70. Fit t h e bonnet.
71. Fit main gear lever gaiter and lever, to previously

marked spline setting. Secure with the

‘Nyloc’ nut (with plain washer) to the correct
torque.

starter motor harness

rear of engine.

72. Fit the cover to both gear levers.
73. Fit the gear lever knobs.
74.

Connect the battery.

OVERHAUL LT77 FIVE

SPEED GEARBOX

(4 cylinder petrol and diesel)

Service Tools:

Bearing remover

Adaptor for mainshaft

Adaptor for layshaft

Remover

for

synchromesh hub and gear

cluster

- Adaptor mainshaft 5th gear

MS47

Hand press

- Adaptor, layshaft bearing remover

-Conversion kit

186284

Impulse extractor

Adaptor for input shaft pilot bearing

track

1861422

Mainshaft rear oil seal replacer

Mainshaft

gear

and

oi! sea!

replacer

Dismantle

1. Place gearbox on a bench with the transfer

gearbox removed, ensuring the oil is first drained.

2. Remove

t h e

clutch release bearing carrier clip.

3. Remove

t h e

clutch release bearing and carrier.

4. Pull the clutch release lever from the clutch

Rcmove the bolts and washers securing the clutch

release lever pivot.

Remove the bolts and washers securing the bell

housing and remove the bell housing.

Remove t h e three bolts and washers retaining

the

gear selector housing to the

fifth

gear extension

case. Lift the housing from the case and discard
the gasket.

Using a suitable pin punch, remove the roll pin
retaining the selector yoke.

9. Push the selector shaft forward to engage a gcar,

and manoeuvre the selector yoke from the shaft.
Return the selector shaft

neutral.

10.

Remove the circlip which retains the mainshaft oil

seal collar located at the rear of the gearbox.

LT77

FIVE SPEED GEARBOX

11. Using tools 186705 and

remove the

oil seal collar.

12. Remove the ten bolts and spring washers securing

the rear cover to the gearcase; withdraw

t h e

rear

cover and discard the gasket.

13. Fit two dummy bolts (8

to the casing

retain the centre plate to the main case.

14. Remove the oil seal collar

ring from the

mainshaft.

15. Withdraw the oil pump drive shaft.
16. Remove the two bolts and spring washers securing

the fifth gear selector fork and bracket.

Withdraw the

fifth

gcar selector spool.

18. Withdraw the fifth gear selector fork and bracket.
19.

On early models, remove circlip retaining fifth

gear (driving) from the layshaft. On later models,
engage reverse gear by turning selector raii anti-

clockwise and pulling rearwards. Move the fifth
speed synchro hub into mesh with the fifth gear.

De-stake the retaining nut securing the fifth gear

iayshaft and remove nut. Select neutral by

pushing selector

inwards and turning

clockwise; and return fifth speed synchro hub to
its out of mesh position.

ST 908M

20. Release the circlip retaining the fifth gear

synchromesh assembly to the mainshaft.

21. Using

tools

and

withdraw the

selective washer, fifth gear synchromesh hub and
cone,

fifth

gear (driven) and spacer from the

mainshaft.

22. Remove the split roller bearing assembly from the

main sh a

23. Using tools 186705 and

remove the

layshaft spacer (if fitted) and layshaft fifth gcar.

24. Remove the selector shaft circlip.
25. Fit suitable guide studs (measuring

8 x

26. Locate t h e gearbox

to a suitable stand.

27. Remove the six bolts and spring washers from the

front cover. withdraw the cover and discard the
gasket.

28. Remove the input shaft and layshaft selective

washers from the gearcase.

29. Remove the two bolts and washers securing the

locating boss for the selector shaft front spool,
withdraw the locating boss.

30. Withdraw the selector plug, spring and ball from

the centre plate.

the main gearbox case.

Content .. 66 67 68 69 ..