Transfer Case Disassemble

Tools Required

• J 3289-20  Holding Fixture
• J 23907  Slide Hammer with Bearing Adapter
• J 26941  Bushing and Bearing Remover - 3-4 inch
• J 45380  Transfer Case Rear Bushing Remover and Installer
• J 45759  Assembly Fixture

IMPORTANT: Because of manufacturing design changes made during this model year, the transfer case was manufactured with either a 1st design rear output shaft and clutch hub or a 2nd design rear output shaft and clutch hub. The 1st design is a loose fit assembly; the clutch hub splines have a clearance fit to the rear output shaft splines and can be assembled or disassembled by hand. The 2nd design is a press fit assembly; the clutch hub splines have an interference fit to the rear output shaft splines and must be assembled or disassembled using a hydraulic press. The 2nd design components can be identified by the following:
• The rear output shaft has an additional groove cut into the shaft between the clutch hub retaining ring groove and the clutch apply plate retaining ring groove.
• The clutch hub has the letter P raised and cast at the rear, 180 degrees from the locator hole.

The 1st design components are not interchangeable with the 2nd design components.
1. Attach the J 45759  to the transfer case using the adapter studs. All of the transfer case disassembly procedures can be performed with the case mounted to the J 45759  .
Fig 1: Installing J 45759 To Transfer Case
Courtesy of GENERAL MOTORS CORP.
2. Mount the J 3289-20  (1) to a sturdy workbench.
3. Install the J 45759  (2) into J 3289-20  (1) and secure with pivot pin.
   Fig 2: View Of Front Transfer Case Bench Mount

   Courtesy of GENERAL MOTORS CORP.
4. Remove the fill plug (1) and the drain plug (2) and drain the transfer case fluid.
   Fig 3: Removing Drain & Fill Plugs

   Courtesy of GENERAL MOTORS CORP.
5. Remove the connector, for the actuator encoder motor wiring harness, from the bracket.
6. Remove the actuator encoder motor mounting bolts.
   Fig 4: Removing Encoder Motor Bolts

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7. Remove the actuator encoder motor assembly.
8. Remove the actuator insulator gasket.
9. Remove the vent and the seal, only if damaged.
   Fig 5: Removing Case Vent & Seal

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10. Remove the rear vehicle speed sensors (VSS).
    Fig 6: Removing Rear Speed Sensors

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11. Remove the front VSS.
    Fig 7: View Of Vehicle Speed Sensor

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12. Remove the access hole plug.
    Fig 8: Removing Rubber Plug

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NOTE: Do not damage the sealing surfaces of the transfer cases or the shafts when prying the seals for removal. Damaging the sealing surface may cause leakage or require replacement of the damaged component.
Fig 9: Removing Input Shaft Seal
Courtesy of GENERAL MOTORS CORP.
13. Remove the input shaft seal by prying it out of the front case.
14. Remove the rear output shaft seal.
    Fig 10: Removing Rear Output Shaft Seal

    Courtesy of GENERAL MOTORS CORP.
15. Inspect the rear output shaft bushing for scoring or wear.
16. Remove the rear output shaft bushing using the J 45380  .
    Fig 11: Removing Rear Output Shaft Bushing

    Courtesy of GENERAL MOTORS CORP.
    1. Install the finger section of the J 45380  in front of the bushing.
    2. Install the tube and forcing screw assembly to the finger section. Ensure the forcing screw is backed out.
    3. Using a wrench on the forcing screw, remove the rear output shaft bushing.
IMPORTANT: The magnesium transfer cases are using new style bolts that have a cup style washer. The cup washer is only available with the bolt. If the cup washer is not damaged, the bolt can be used again.
Fig 12: Removing Case Half Bolts/Studs With Cup Washers
Courtesy of GENERAL MOTORS CORP.
17. Remove the transfer case retaining bolts and washers.

    Mark the location of any brackets.

NOTE: Do not nick, scratch or damage the sealing surface. The sealing surface is a machined surface. Damage to the machined surface can cause leakage.
Fig 13: Locating Slot On Left Side Of Transfer Case
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18. Insert a flat-blade screwdriver into the slot on the left side of the transfer case.
19. Insert a flat-blade screwdriver into the slot on the right side of the transfer case.
    Fig 14: Locating Slot On Right Side On Transfer Case

    Courtesy of GENERAL MOTORS CORP.
20. With equal pressure, press down on the screwdrivers in order to separate the front case half and the rear case half.
21. Insert a pair of snap ring pliers and release the outer retaining ring for the rear output shaft bearing.
    Fig 15: Using Snap Ring Pliers To Release Outer Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
22. Remove the rear case half from the front case half.
    Fig 16: Separating Case Halves

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23. Remove the oil pump wear sleeve, only if worn or damaged.
    Fig 17: Removing Oil Pump Wear Sleeve

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24. Remove the rear output shaft rear bearing retaining ring.
    Fig 18: Removing Rear Output Shaft Bearing Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
25. Remove the rear output shaft rear bearing.
    Fig 19: Removing Rear Output Shaft Bearing

    Courtesy of GENERAL MOTORS CORP.
26. Remove the rear output shaft speed sensor reluctor wheel.
    Fig 20: Removing Rear Output Shaft Speed Sensor Reluctor Wheel

    Courtesy of GENERAL MOTORS CORP.
27. Remove the oil pump suction pipe assembly. Do not remove the screen from the pipe.
    Fig 21: Removing Oil Pump Suction Pipe Assembly

    Courtesy of GENERAL MOTORS CORP.
28. Remove the magnet.
    Fig 22: Removing Magnet

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29. Remove the oil pump wave spring.
30. Remove the oil pump assembly.
    Fig 23: Oil Pump Assembly

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31. Remove the oil pump suction pipe O-ring from the oil pump.
    Fig 24: Removing Oil Pump Suction Pipe O-Ring

    Courtesy of GENERAL MOTORS CORP.
32. Remove the drive sprocket retaining ring.
    Fig 25: Removing Drive Sprocket Retaining Ring

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33. Remove the driven sprocket retaining ring.
    Fig 26: Removing Driven Sprocket Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
IMPORTANT: If the chain and sprockets are to be used again, mark the relationship of the chain to the sprockets in order to mark the wear patterns.
Fig 27: Removing Drive Chain & Sprockets
Courtesy of GENERAL MOTORS CORP.
34. Remove the chain and sprockets.
35. Remove the chain from the drive sprocket and driven sprocket.
36. Remove the rear output shaft assembly.
    Fig 28: Removing Rear Output Shaft Assembly

    Courtesy of GENERAL MOTORS CORP.
37. Mount the rear output shaft assembly, with the input end up, in a soft-jaw vise.
38. Remove the clutch assembly retaining ring. Push down on the clutch apply plate to access the retaining ring.
    Fig 29: Removing Clutch Assembly Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
39. Remove the clutch apply plate assembly.
    Fig 30: Removing Clutch Apply Plate Assembly

    Courtesy of GENERAL MOTORS CORP.
40. Remove the clutch return spring.
41. Remove the clutch apply plate bearing and inner support from the clutch apply plate.
    Fig 31: Removing Clutch Pressure Plate Bearing With The Inner Support

    Courtesy of GENERAL MOTORS CORP.
42. Inspect the bearing for being faulty. Refer to Cleaning and Inspection .
43. If the bearing is faulty, using a hydraulic press and a suitable adapter, remove the clutch apply plate bearing from the clutch bearing inner support.
    Fig 32: Removing Clutch Pressure Plate Bearing From Clutch Bearing Inner Support

    Courtesy of GENERAL MOTORS CORP.
44. Discard the bearing after removal.
45. Remove the clutch hub retaining ring.
    Fig 33: Removing Clutch Hub Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
46. If 1st design, remove the clutch housing and hub assembly from the rear output shaft.
IMPORTANT: Do not press against the outer portion of the clutch housing (2).
Fig 34: Removing Clutch Housing And Hub Assembly Components
Courtesy of GENERAL MOTORS CORP.
47. If 2nd design, reinstall the drive sprocket (3) to the clutch housing (2). The drive sprocket (3) will be used to press against.
48. If 2nd design, place the rear output shaft assembly into a hydraulic press with the input end facing up and the drive sprocket (3) supporting the assembly against the hydraulic press blocks (4).
IMPORTANT: A maximum of 3 200 kg (7,055 lb) may be necessary to remove the rear output shaft (1) from the clutch hub.
49. If 2nd design, press the rear output shaft (1) from the clutch hub.
50. Turn the clutch assembly over on a workbench.
    Fig 35: Removing Clutch Assembly Components, 2nd Design

    Courtesy of GENERAL MOTORS CORP.
51. Remove the clutch housing.
IMPORTANT: Do not remove the oil restrictor plate. The oil restrictor plate is only serviced with the clutch hub.
52. Remove the clutch hub.
IMPORTANT: Do not wash the clutch inner friction plates in cleaning solvent.
Fig 36: Removing Clutch Plates
Courtesy of GENERAL MOTORS CORP.
53. Separate the clutch plates for inspection.
54. Remove and discard the shim or shims.
55. Remove the oil restrictor from the rear output shaft, if replacing the shaft.
    Fig 37: Removing Rear Output Shaft Oil Restrictor

    Courtesy of GENERAL MOTORS CORP.
56. Inspect the bearing in the clutch housing for being faulty. Refer to Cleaning and Inspection .
    Fig 38: Removing Bearing In The Clutch Housing

    Courtesy of GENERAL MOTORS CORP.
57. If the bearing is faulty, use a brass drift and a hammer to remove the bearing.
58. Remove both of the clutch lever pivot pins with the aluminum washers and the O-ring seals.
    Fig 39: Removing Clutch Lever Pivot Pin

    Courtesy of GENERAL MOTORS CORP.
59. Remove the clutch lever assembly from the control actuator lever.
    Fig 40: Removing Clutch Lever Assembly

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60. Remove the shift fork shaft.
    Fig 41: Removing Shift Fork Shaft

    Courtesy of GENERAL MOTORS CORP.
61. Remove the range shift fork and the range shift sleeve as an assembly.
    Fig 42: Removing Range Shift Fork & Range Shift Sleeve

    Courtesy of GENERAL MOTORS CORP.

    It may be necessary to lightly pry the roller on the shift fork from the control actuator lever.

62. Remove the range shift sleeve from the range shift fork.
    Fig 43: Removing Range Shift Sleeve From Range Shift Fork

    Courtesy of GENERAL MOTORS CORP.
63. Remove the input gear bearing outer retaining ring.
    Fig 44: Removing Input Gear Bearing Outer Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Depending on the version of the transfer case, it may have either a 3 pinion gear or 6 pinion gear planetary carrier assembly. The 3 pinion gear planetary carrier is used with transmission RPO M30 and the input gear splines are 27 teeth. The 6 pinion gear planetary carrier is used with transmission RPO MT1 and MN8 and the input gear splines are 32 teeth. The repair procedures are the same for both planetary carriers.
Fig 45: Removing Planetary Gear Carrier
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64. Remove the high/low planetary carrier.
65. Remove the planetary gear shaft retaining ring.
    Fig 46: Removing Planetary Gear Shaft Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
66. Remove the planetary carrier lock ring.
    Fig 47: Removing Planetary Carrier Lock Ring

    Courtesy of GENERAL MOTORS CORP.
67. Remove the input gear front thrust washer.
    Fig 48: Removing Input Gear Front Thrust Washer

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68. Remove the input gear from the planetary carrier.
    Fig 49: Removing Input Gear

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69. Remove the input gear rear thrust washer.
    Fig 50: Removing Input Gear Rear Thrust Washer

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70. Inspect the pilot bearing in the input gear for being faulty. Refer to Cleaning and Inspection .
    Fig 51: Removing Pilot Bearing From Input Gear

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71. Remove the pilot bearing from the input gear using a brass drift and a hammer.
    Fig 52: Removing Front Output Shaft Bearing Inner Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
72. Remove the inner retaining ring for the front output shaft bearing.
73. Using a soft-face hammer, remove the front output shaft, with the bearing, from the front case half.
    Fig 53: Removing Front Output Shaft With Bearing

    Courtesy of GENERAL MOTORS CORP.
74. Using a suitable punch, remove the front output shaft seal from the front case half.
    Fig 54: Removing Front Output Shaft Seal

    Courtesy of GENERAL MOTORS CORP.
75. Remove the outer retaining ring for the front output shaft bearing.
    Fig 55: Removing Front Output Shaft Bearing Outer Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
76. Inspect the front output shaft bearing for being faulty. Refer to Cleaning and Inspection .
    Fig 56: Removing Front Output Shaft Bearing

    Courtesy of GENERAL MOTORS CORP.
77. Remove the bearing from the front output shaft. Do not use the bearing again after removal.
78. If damaged, remove the speed sensor reluctor wheel from the front output shaft, using a hydraulic press. Do not use the speed sensor reluctor wheel again after removal.
    Fig 57: Removing Speed Sensor Reluctor Wheel

    Courtesy of GENERAL MOTORS CORP.
79. If the cup plug in the front output shaft is leaking, remove the plug using a brass drift.
    Fig 58: Removing Cup Plug

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80. Remove the input bearing retaining ring.
    Fig 59: Removing Input Bearing Retaining Ring

    Courtesy of GENERAL MOTORS CORP.
81. Remove the input bearing.
    Fig 60: Removing Input Bearing

    Courtesy of GENERAL MOTORS CORP.
82. Inspect the front output shaft rear bearing for being faulty. Refer to Cleaning and Inspection .
83. If the bearing is faulty, remove the bearing using the J 23907  (2) and the J 26941  (1).
    Fig 61: Removing Front Output Shaft Rear Bearing With J 23907 & J 26941

    Courtesy of GENERAL MOTORS CORP.
84. Remove the control actuator lever shaft retaining ring.
    Fig 62: Removing Control Actuator Lever Shaft Retaining Ring

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85. Remove the control actuator lever shaft.
    Fig 63: Removing Control Actuator Lever Shaft

    Courtesy of GENERAL MOTORS CORP.
86. Inspect the control actuator lever bearing and seal for being faulty. Refer to Cleaning and Inspection .
87. If the bearing is leaking or faulty, remove the bearing from the case.