1. Disconnect battery
2. Elevate truck
3. Spray cross-member and skid plate bolts with rust breaker
4. Disconnect rear drive shaft at third member
5. Remove the transmission skid plate [see Skidplates on]
6. Drain transfer case fluid & transmission fluid, replacing
both plugs. Check the magnet on the drain plug for any metal particles.
[see Oil draining]
7. Disconnect speedometer cable
8. Remove rear driveshaft
9. Disconnect both shift levers
10. Disconnect front drive shaft (drop both ends to fully remove)
11. Remove the nuts from the transmission mount cross-member
NOTE: on the v6 equipped Troopers the starter doesn't bolt to
the bell housing. Owners of 4cyl Troopers and other models should
check for this.
12. Attach the transmission jack
13. Remove cross-member frame bolts
14. Remove catalytic converter and crossover Y pipe
15. Disconnect transfer case indicator & reverse sensors
16. Disconnect slave cylinder (see photo)
17. Remove bell housing bolts except top one (watch for hidden
bolt on driver's side for dust shield-this one uses front access)
18. Attach chain from transmission lift
19. Remove final bell housing bolt
20. Carefully lower the transmission/transfer case assembly [see
NOTE: For late automatics with electronic four-wheel drive shifters,
remove the front wheel drive electric shift. (See the Isuzu shop
manual for the removal procedure.)
21. Clean exterior thoroughly (it is critical to avoid introducing
gunk into the transfer case assembly), plugging the output shaft
the nine bolts and the two stud bolts from the housing.
NOTE: Mark the location where the two stud bolts were removed
for assembly later.
23. Use a small ball peen hammer on flanges at the seal to crack
sealant and separate the transfer case from the transmission case
(6-12 gentle to medium hard blows per side may be necessary).
Tera recommends prying, however the latter method was sufficient
to allow only very easy prying for the final separation.
NOTE: The two locating dowel pins and all the internal shafts
(except the rear wheel drive shaft) stay with the front half of
the housing. There will be no changes made on the rear half of
the snap ring on the input shaft.
25. Pull spring
& ball with magnetic rod from transfer shifter cavity
Use caution as the hi-lo sync gear can fall off at this point.
26. Use a 3/16"
wide by 3/32" thick tool to pry out the hammered-in portion
of the nut at the key slot. Remove the nut.
27. Remove the high-low speed ball detent unit. (This is a 3/4"
hex. fitting that is located on the outside of the housing inline
with the shift rail shaft) Remove the hex, fitting, spring and
ball. DO NOT leave the ball in the hole, as it will fall into
the rail shaft hole when the shaft is removed.
NOTE: Do not remove the ball detent unit for the front wheel engagement
28. Pull main shaft ball bearing.
stake on end lock nut.
Remove end lock nut
31. Remove front outer (large) nut on front output shaft (exterior
hi-lo synchronizer assembly.
NOTE: The above requires a rather odd puller combination-in our
case it meant purchasing just the right one for reach, spread
and tip ends.
the snap ring that is under the gear on the idler shaft. This
is the snap ring that holds the idler shaft to the housing. (This
snap ring will remain loose around the idler shaft but will allow
the idler shaft to move outward.)
34. NOTE: keys may fall out at this point
35. Place puller around (6) and NOT the syncro, which can be damaged.
snap ring (11) may bind the shaft (24) from coming out enough
to remove (6)
NOTE: The idler shaft may have to be pulled up slightly to clear
the yoke's removal. If the roller bearing and the inner bearing
sleeve pull up with the assembly, make sure that you do not loose
the inner bearing sleeve's drive ball that is located in the input
37. Remove the idler shaft. Pull up by hand. [see Main shaft alone]
38. Remove the snap ring on the idler shaft.
39. Remove the ball bearings from the idler shaft.
40. Check for wear on brass syncro ring (5)
41. Check all of the ball bearings for wear and smooth running.
42. Check low speed gear's roller bearing for pits and wear.
43. Check the inner bearing sleeve for pits and wear.
44. Make sure that all the gasket material is removed and remove
all nicks and burrs on the mating surfaces of all the parts.
45. Press bearings off of the counter gear
46. Screw the OEM nut on the input shaft and torque to 60 foot
lbs. Stake the flange on the nut into the slot.
47. Press the #6305 ball bearing on the input shaft and assemble
the snap ring.
48. Assemble the high-low ball detent unit. (Ball, spring and
3/4" hex fitting)
49. Check all shifting action and gear rotation.
50. Apply a minimal layer of gray silicone sealant on both parts
of the housing [see Adding Sealant]. Assemble the housings and
screw in the 11 bolts, torque to 50 foot lbs.
51. Lubricate the bearing surfaces on the idler shaft and press
# 83 A4600 ball bearing and # 6306 ball bearing on the shaft to
NOTE: NO groove is provided for the rear of the shaft (i.e., 27).
52. Install the OEM snap ring on the idler shaft. (# 6306 Bearing).
53. Insert the assembled idler shaft in the front half of the
54. If the inner roller bearing sleeve and drive ball has been
removed, put some grease around the drive ball and place the drive
ball in the hole in the input shaft that was made for it. Slide
the inner roller bearing sleeve on the input shaft making sure
that the drive ball is in its slot.
55. Assemble the roller bearing and the low speed gear on the
roller bearing sleeve. Rotate the gear train to make sure that
it turns free.
56. Tap out the roll pins (One inside the other) from the yoke
and the OEM shift rail shaft. Assemble the OEM yoke on the shift
rail TL 307-3 shaft
The rotation of the yoke to centerlines of the ball detent must
the yoke and shift rail assembly into its hole, making sure that
the vacuum activated shift shaft is correctly installed. Check
to see if this assembly moves up and down freely.
Lift the yoke assembly up enough so that you can slide the shift
ring on the yoke, drop the yoke so that the shift ring will engage
with the gear.
58. Using snap-ring pliers or long needle-nose pliers, put the
snap ring in its groove in the housing.
59. Press the splined drive shaft part onto the input shaft until
it seats on the inner roller bearing sleeve. Rotate the gear train
to make sure that it turns free.
60. Replace assembly on main shaft
NOTE: Be sure that the keys line up
61. Reattach "C" clip on front output shaft (11)
62. Reattach new main shaft nut at approximately 100 pounds of
torque [see Reassembly]
63. Reattach snap ring (25) [see Wrestling C clip]
NOTE: The latter proved to be very tricky due to access issues
resulting from the new large gear and how it precluded reaching
the snap ring. This proved to be the most challenging part of
64. Assemble cases by gently tapping on flanges. Use caution regarding
movement in the vent slide shield, which can move and impede the
case's seal. This may require a few tries to get the shift rail
to line up if you do not align it with the pin angle back in the
case's hole (tunnel) for the same rail. [see Tapping cases together]
65. Until the detent spring/ball and 4x4 sensor are back in the
assembly may not shift smoothly
66. Replace output shaft seal.
NOTE: Stud bolts to be installed where marked,
67. Bolt on the high-low shift unit.
68. Mount the front wheel drive shift unit. (See the Isuzu shop
manual on how to install and to set the gear timing.)
69. Screw in the oil plugs.
70. Assemble in vehicle, add oil. torque all components to specifications.
NOTE: If boot on slave cylinder is torn this will be a good time
to replace it.
Isuzu oil seal #8-97046-701-2
Isuzu transmission oil seal #8-94422-387-0
Isuzu front output shaft nut #8-94422-073-0
Isuzu main shaft lock nut #8-94422-072-1
AND CONCLUSION --->>>