Transfer Case Assemble

Tools Required

• J 3289-20  Holding Fixture
• J 8092  Universal Driver
• J 8614-01  Flange and Pulley Holding Tool
• J 35582  Oil Pump Seal Installer. See Special Tools .
• J 36371  Output Shaft Bearing Installer. See Special Tools .
• J 36850  Transjel Lubricant
• J 37212  Front Output Shaft Seal Installer. See Special Tools .
• J 45759  Assembly Fixture. See Special Tools .
• J 45933  Isuzu Transfer Case Assembly/Disassembly Kit. See Special Tools .
• J 45934  Input Seal Installer. See Special Tools .
• J 45936  Control Actuator Shaft Bushing Installer. See Special Tools .
• J 45937  Rear Output Shaft Retaining Ring Installer. See Special Tools .
• J 46199  Front Output Shaft Bearing Remover and Installer. See Special Tools .

Fig 1: View Of 2/4 Shift Fork And Spring On The Shift Shaft
Courtesy of GENERAL MOTORS CORP.
1. If disassembled, install the 2/4 shift fork and spring on the shift shaft.
Fig 2: Locating 2/4 Shift Fork Retaining Ring
Courtesy of GENERAL MOTORS CORP.
2. Compress the spring on the 2/4 shift fork in a vise.
3. Install the retaining ring.
Fig 3: Locating Roll Pin On High/Low Shift Fork
Courtesy of GENERAL MOTORS CORP.
4. If disassembled, install the high/low shift fork on the shift shaft. Position the fork, as shown, on the shift shaft.
5. Install the roll pin in the shift fork until flush.
Fig 4: View Of Shift Block Components
Courtesy of GENERAL MOTORS CORP.
6. Install the spring seat (252), the spring (253) and the block collar (254) in the shift block (256).
Fig 5: View Of Shift Rail Inner Retaining Ring
Courtesy of GENERAL MOTORS CORP.
7. Install the inner retaining ring over a socket.
8. Install the socket and the block in a vise to compress the spring.
9. Install the inner retaining ring in the block.
Fig 6: View Of Shift Rail Retaining Ring
Courtesy of GENERAL MOTORS CORP.
10. Using a vise, compress the spring in the high/low shift block.
11. Install the retaining ring on the shift rail.
Fig 7: Locating Vent/Breather Hose Pipes
Courtesy of GENERAL MOTORS CORP.
12. If removed, using retaining compound GM P/N 12377901 (Canadian P/N 10953504) or equivalent, install the vent or breather hose pipes. Ensure the pipes are properly aligned.
Fig 8: Mounting Front Case Half To J 45759
Courtesy of GENERAL MOTORS CORP.
13. Mount the front case half to the J 45759  with 4 bolts. See Special Tools .
14. Install the J 45759  (2) into the J 3289-20  (1). See Special Tools .
Fig 9: Installing Control Actuator Shaft Bushing With J 45936
Courtesy of GENERAL MOTORS CORP.
15. If removed, using the J 45936  , install the control actuator shaft bushing. See Special Tools .
Fig 10: View Of Breather Baffle & Retaining Bolt
Courtesy of GENERAL MOTORS CORP.
NOTE: Refer to Fastener Notice .
16. If removed, install the breather baffle and bolt.

    Tighten:  Tighten the breather baffle bolt to 6.5 N.m (58 lb in).

Fig 11: Identifying J 36371
Courtesy of GENERAL MOTORS CORP.
17. Using the J 36371  , install a new front output shaft front bearing in the front case half. See Special Tools .
Fig 12: View Of Front Output Shaft Front Bearing Retaining Ring
Courtesy of GENERAL MOTORS CORP.
18. Install a new retaining ring for the front output shaft front bearing.
Fig 13: Identifying Carrier Bearing Outer Retaining Ring
Courtesy of GENERAL MOTORS CORP.
19. Install the carrier bearing outer retaining ring in the front case half.
Fig 14: Locating Annulus Gear Damper
Courtesy of GENERAL MOTORS CORP.
20. Lubricate the annulus gear damper with transfer case fluid.
21. Install the damper in the case.
Fig 15: View Of Annulus Gear
Courtesy of GENERAL MOTORS CORP.
22. Install the annulus gear in the front case. Ensure the damper is still in the correct position.
Fig 16: Compressing Annulus Gear Damper With J 45933 Components
Courtesy of GENERAL MOTORS CORP.
23. Using the J 45933-2 (1) and the J 45933-3 (2) of the J 45933  , compress the damper under the annulus gear. See Special Tools .
    • Use the J 45933-2 (1) with the step in the annulus gear.
    • Use the J 45933-3 (2) in the bore of the input seal.
    • Compress the damper until the groove for the annulus retaining ring is exposed.
Fig 17: View Of Spiral Retaining Ring For Annulus Gear
Courtesy of GENERAL MOTORS CORP.
24. Install the spiral retaining ring for the annulus gear.
25. Remove the J 45933  and ensure the spiral retaining ring is fully seated. See Special Tools .
Fig 18: Installing Input Shaft Bearing With J 45933-1 & J 45933-2
Courtesy of GENERAL MOTORS CORP.
26. Using the J 45933-1 (1) and the J 45933-2 (2) of the J 45933  , install the input shaft bearing in the planetary carrier. See Special Tools .
    • For ease of installing the bearing, use a vise to hold the nut and the threaded shaft.
    • Stack the J 45933-2 and the planetary carrier over the threaded shaft.
    • In order to install the input shaft bearing at the proper depth, use the side of the J 45933-1 with the step against the bearing.
Fig 19: Identifying J 45933-3 & J 45933-2
Courtesy of GENERAL MOTORS CORP.
27. Using the J 45933-3 (1) and the J 45933-2 (2) of the J 45933  , install the bearing on the planetary carrier. See Special Tools .
    • The retaining ring groove on the bearing goes toward the planetary carrier.
    • For ease of installing the bearing, use a vise to hold the nut and the threaded shaft.
    • Stack the J 45933-2 and the planetary carrier over the threaded shaft.
Fig 20: Identifying Planetary Carrier Bearing Retaining Ring
Courtesy of GENERAL MOTORS CORP.
28. Install the planetary carrier bearing retaining ring.
Fig 21: Locating Input Shaft Thrust Bearing
Courtesy of GENERAL MOTORS CORP.
29. Install the input shaft thrust bearing.
Fig 22: View Of Input Shaft In Planetary Carrier Assembly
Courtesy of GENERAL MOTORS CORP.
30. Install the input shaft in the planetary carrier assembly.
Fig 23: Identifying Planetary Carrier Low Gear Components
Courtesy of GENERAL MOTORS CORP.
31. If using the planetary carrier and planetary carrier low gear again, align the marks from disassembly.
32. Install the planetary carrier low gear. The side with the thrust surface faces toward the input shaft.
33. Install the planetary carrier low gear retaining ring.
Fig 24: Spreading Carrier Bearing Retaining Ring
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Ensure the snap ring pliers do not catch on the ribs of the case. The retaining ring must be fully opened and retracted in the groove.
34. Using a large pair of snap ring pliers, spread the carrier bearing retaining ring.
35. While the retaining ring is spread, install the planetary carrier assembly.
36. Ensure the retaining ring is secured on the planetary carrier bearing.
Fig 25: Identifying Rear Output Shaft Front Support Bearing
Courtesy of GENERAL MOTORS CORP.
37. Install the rear output shaft front support bearing.
38. Using J 36850  , pack the bearing.
Fig 26: View Of 2/4 Synchronizer Hub On Rear Output Shaft
Courtesy of GENERAL MOTORS CORP.
39. Using a hydraulic press, install the 2/4 synchronizer hub.
    • The non-shoulder side of the hub aligns to the rear of the rear output shaft.
    • Ensure the hub is supported on the shoulder flange, not on the external hub teeth.
Fig 27: View Of Synchronizer Hub Retaining Ring
Courtesy of GENERAL MOTORS CORP.
40. Install the synchronizer hub retaining ring.
Fig 28: Aligning Rear Spring Ends By The Insert Slots
Courtesy of GENERAL MOTORS CORP.
41. Install the rear spring on the synchronizer hub.
42. Align the spring ends by the insert slots.
43. Install the front spring, with the ends opposite from the rear spring, on the synchronizer hub.
44. Align the spring ends by the insert slots.
Fig 29: Checking Synchronizer Sleeve Groove Alignment
Courtesy of GENERAL MOTORS CORP.
45. Install the three synchronizer inserts in the synchronizer hub.
46. Install the synchronizer sleeve.
    • The sleeve shoulder with the groove aligns forward.
    • Align the flat teeth of the sleeve with the insert.
    • Push in on the inserts.
Fig 30: High/Low Range Sleeve
Courtesy of GENERAL MOTORS CORP.
47. Install the high/low range sleeve.
Fig 31: Aligning Shift Blocks On High/Low Shift Fork Assembly & 2/4 Shift Fork Assembly
Courtesy of GENERAL MOTORS CORP.
48. Install the high/low shift fork assembly (255) to the high/low range sleeve.
49. Install the 2/4 shift fork assembly (243) to the 2/4 synchronizer sleeve.
50. Align the shift blocks as shown.
Fig 32: Identifying Rear Output Shaft
Courtesy of GENERAL MOTORS CORP.
51. Lubricate the shift shaft holes in the front case with transfer case fluid.
52. Install the rear output shaft, with the shift forks, to the front case half.
    • Hold the shift forks in position to the sleeves.
    • Install the shift shafts in the holes in the case.
    • Align the high/low range sleeve teeth with the planetary low gear teeth.
Fig 33: Identifying Shift Fork Rollers
Courtesy of GENERAL MOTORS CORP.
53. Install the rollers on the shift forks.
Fig 34: View Of Control Actuator Cam
Courtesy of GENERAL MOTORS CORP.
54. Install the control actuator cam. The smaller recess on the cam goes up and faces toward the shift rails.
55. Rotate the control actuator cam to align to the shift forks.
56. Install the control actuator shaft. Align the large spline on the shaft with the large groove in the cam.
Fig 35: Locating 2/4 Synchronizer Inner, Middle & Blocking Ring
Courtesy of GENERAL MOTORS CORP.
57. Install the 2/4 synchronizer blocking ring. Align the tabs on the ring with the insert grooves on the synchronizer hub.
58. Install the 2/4 synchronizer middle ring.
59. Install the 2/4 synchronizer inner ring.
Fig 36: Installing Chain On Drive Sprocket & Driven Sprocket
Courtesy of GENERAL MOTORS CORP.
60. Lubricate the journal on the rear output shaft, for the drive sprocket, with transfer case fluid.
61. With the blue link pointing to the rear case, install the chain on the drive sprocket and the driven sprocket.
62. Install the chain, the front output shaft and the drive gear.
63. Rotate the drive gear to align with the tabs on the 2/4 synchronizer rings.
64. Inspect to ensure the drive gear and the rear output shaft assembly are installed properly. View the chain from the side. The chain links will be parallel to the case sealing flange. If the chain links are not parallel to the case, disassemble until the condition is found.
Fig 37: View Of Drive Gear Thrust Washer
Courtesy of GENERAL MOTORS CORP.
65. Install the drive gear thrust washer. Align the thrust washer teeth with the flat area on the rear output shaft.
Fig 38: Checking Drive Sprocket Retaining Ring Fit
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: The drive sprocket retaining rings are select fit. Use only a new retaining ring.
66. Select the thickest drive sprocket retaining ring that will fit in the groove. Four sizes are available.
67. Install the drive sprocket retaining ring.
68. Measure the retaining ring outside diameter. If the measured diameter is larger than the specified range, use a thinner retaining ring.

    Specification:  Retaining ring outside diameter: 53.0 +/- 0.5 mm (1.969 +/- 0.020 in)

Fig 39: Aligning Holes In Bushing With Oil Grooves In Case
Courtesy of GENERAL MOTORS CORP.
IMPORTANT:
• Use the thrust bearing between the J 45933-4 (1) and a washer.
• Ensure the threads of the threaded shaft on the J 45933  are lubricated with the supplied lubricant. See Special Tools .
69. If removed, install the rear bushing in the rear case, using the J 45933-4 (1) and the J 45933-3 (2) of the J 45933  . See Special Tools .
    • Align the holes of the bushing with the oil grooves in the case.
    • The bushing installed depth is just past the shoulder in the case.
Fig 40: View Of Shift Shaft Plugs
Courtesy of GENERAL MOTORS CORP.
70. If necessary, install the shift shaft plugs. Use threadlocker GM P/N 12345382 (Canadian P/N 10953489) or equivalent on the plugs.
Fig 41: Installing Front Output Shaft Rear Bearing With J 8092 & J 46199
Courtesy of GENERAL MOTORS CORP.
71. Using J 8092  (1) and J 46199  (2), install the front output shaft rear bearing. See Special Tools . The part numbers on the bearing align away from the case and toward the tool.
Fig 42: Aligning Speed Sensor Reluctor Wheel
Courtesy of GENERAL MOTORS CORP.
72. Position the speed sensor reluctor wheel in the rear case half, with the oil grooved side toward the inside of the rear case half.
Fig 43: Installing Rear Output Shaft Bearing
Courtesy of GENERAL MOTORS CORP.
73. Install the rear output shaft bearing in the rear case half, using the J 45933-3 (1) and the J 45933-1 (2) of the J 45933  . See Special Tools .
    • Use the single shoulder side of the J 45933-3 in the rear seal bore.
    • Ensure the bearing is being installed square to the bearing bore.
    • Install the bearing until it bottoms in the bearing bore.
Fig 44: Locating Rear Output Shaft Bearing Retaining Ring
Courtesy of GENERAL MOTORS CORP.
74. Install the rear output shaft bearing retaining ring.
Fig 45: Identifying Oil Pump Wire Retaining Ring
Courtesy of GENERAL MOTORS CORP.
75. Install the oil pump wire retaining ring, with the ends aligning in the larger open area of the bore.
Fig 46: View Of Oil Pump Components
Courtesy of GENERAL MOTORS CORP.
76. Prelube the oil pump.
    1. Pour a small quantity of transfer case fluid in the oil suction pipe fitting.
    2. Rotate the oil pump gear a few turns.
77. Install the oil pump suction hose to the oil pump.
78. Install the oil pump suction hose to the oil pump screen.
Fig 47: Locating Oil Pump With Screen
Courtesy of GENERAL MOTORS CORP.
79. Install the oil pump, with the screen, in the rear case half. Push on the oil pump and it will snap into position.
80. Install the oil pump suction tube bolt.

    Tighten:  Tighten the suction tube bolt to 15 N.m (11 lb ft).

Fig 48: View Of Oil Deflector
Courtesy of GENERAL MOTORS CORP.
81. Install the oil deflector and bolts.

    Tighten:  Tighten the deflector bolts to 15 N.m (11 lb ft).

Fig 49: Identifying Sealant Areas On Sealing Flange
Courtesy of GENERAL MOTORS CORP.
NOTE: Apply the proper amount of sealant to the flange when assembling the transfer case. Excessive amounts of sealant can plug the oil pump screen, resulting in internal component failure.
IMPORTANT:
• Ensure that the sealing surfaces of the front and rear case halves are free of dirt, oil and cleaning solvent.
• Ensure the locating pins are installed in the front case half. Install the locating pins if necessary.
82. Apply a 3 mm (1/8 in) bead of flange sealant GM P/N 12378517 (Canadian P/N 88900757) to the sealing flange on the rear case half. Apply the sealer evenly to the inside surface of the bolt holes, with no gaps.
Fig 50: View Of Front Case & Rear Case
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: The locating pins must be installed in the front case half.
83. If necessary, install the locating pins in the front case half.
84. Install the rear case half.
    • Rotate the input shaft to allow the rear output shaft to align with the speed sensor reluctor wheel splines.
    • Lightly tap down on the rear case half to fully install on the locating pins.
Fig 51: View Of Transfer Case Half Bolts
Courtesy of GENERAL MOTORS CORP.
85. Install the case half bolts.

    Tighten:  Tighten the case half bolts to 22 N.m (16 lb ft).

Fig 52: Installing Rear Output Shaft Retaining Ring
Courtesy of GENERAL MOTORS CORP.
86. Position a new rear output shaft retaining ring over the rear output shaft.
IMPORTANT: Push inward against the input shaft to expose the retaining ring groove and allow the retaining ring to seat fully into the groove.
87. Using the J 45937  , install the retaining ring. See Special Tools . Tap lightly, or use hand pressure on the J 45937  until the retaining ring installs in the groove. See Special Tools .
Fig 53: View Of Rear Output Shaft Seal
Courtesy of GENERAL MOTORS CORP.
88. Using the J 35582  with a hammer, install the rear output shaft seal. See Special Tools .
Fig 54: View Of Control Actuator Shaft Seal (Spring Side Toward The Inside)
Courtesy of GENERAL MOTORS CORP.
89. Install the control actuator shaft seal flush to the case surface. The spring side installs to the inside.
Fig 55: Locating J 45934
Courtesy of GENERAL MOTORS CORP.
90. Using the J 45934  with a hammer, install the input shaft seal. See Special Tools .
Fig 56: View Of J 37212 & Front Output Shaft Seal
Courtesy of GENERAL MOTORS CORP.
91. Using the J 37212  with a hammer, install the front output shaft seal. See Special Tools .
Fig 57: View Of Detent Plugs, Springs & Balls
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Depending on design levels, this transfer case may or may not have an additional spring nesting inside the high/low shift shaft detent.
92. Install the detent springs and balls.
93. Apply GM P/N 12346004 (Canadian P/N 10953480) to the threads on the detent plugs.
94. Install the detent plugs.

    Tighten:  Tighten the detent plugs to 19 N.m (14 lb ft).

Fig 58: View Of Yoke Flange Components
Courtesy of GENERAL MOTORS CORP.
95. Install the yoke flange on the front output shaft.
96. Lightly lubricate a new yoke flange O-ring with transfer case fluid.
97. Install the yoke flange O-ring.
98. Install a new yoke flange nut.
Fig 59: View Of J 8614-01 & Yoke Flange Nut
Courtesy of GENERAL MOTORS CORP.
99. Install the J 8614-01  to assist in tightening the yoke flange nut.

    Tighten:  Tighten the yoke flange nut to 137 N.m (101 lb ft).

Fig 60: Identifying Yoke Flange Nut Staking Areas
Courtesy of GENERAL MOTORS CORP.
100. Remove the J 8614-01  .
101. Using a suitable punch, stake the yoke flange nut in 2 places.
Fig 61: Locating 2/4 Switch Assembly & NEUTRAL Start Switch
Courtesy of GENERAL MOTORS CORP.
102. Install the 2/4 switch assembly (316) with the copper gasket. The 2/4 switch has the gray wiring harness connector.

     Tighten:  Tighten the 2/4 switch to 39 N.m (29 lb ft).

103. Install the NEUTRAL start switch (307) with the copper gasket. The NEUTRAL start switch has the brown wiring harness connector.

     Tighten:  Tighten the NEUTRAL switch to 39 N.m (29 lb ft).

Fig 62: Identifying Connector Bracket Bolt
Courtesy of GENERAL MOTORS CORP.
104. Install the switch connector bracket and spacer.
105. Install the connector bracket bolt.

     Tighten:  Tighten the connector bracket bolt to 15 N.m (11 lb ft).

106. Install the wiring harness connectors, for the switches, into the switch connector bracket.
Fig 63: View Of Actuator Assembly
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Do not rotate the actuator assembly shaft to align with the control actuator shaft.
107. Install the actuator assembly and the new O-ring seal.
108. Install the actuator assembly bolts and wire harness bracket.

     Tighten:  Tighten the actuator assembly bolts to 22 N.m (16 lb ft).

Fig 64: Locating Vent Hose & Breather Hose
Courtesy of GENERAL MOTORS CORP.
109. Install the vent hose to the actuator assembly.
110. Install the breather hose.
Fig 65: Identifying Vehicle Speed Sensor (VSS)
Courtesy of GENERAL MOTORS CORP.
111. Install the vehicle speed sensor (VSS) and O-ring seal.

     Tighten:  Tighten the VSS to 17 N.m (13 lb ft).

Fig 66: View Of Drain & Fill Plugs
Courtesy of GENERAL MOTORS CORP.
112. Install a new O-ring gasket on the drain plug and the fill plug.
113. Install the drain plug (15) and the fill plug (10).

     Tighten:  Tighten the drain plug and fill plug to 39 N.m (29 lb ft).

114. Remove the transfer case from the J 3289-20  .
115. Remove the J 45759  from the transfer case. See Special Tools .