4. Transfer Case Assemble
Transfer Case AssembleAssembly Procedure
^ Tools Required
- J 8092 Universal Handle
- J 36370 Drive Sprocket Needle Bearing Installer
- J 36373 Input Sun Gear Ball Bearing Installer
- J 36850 Transjel Lubricant
- J 37668-A Seal Installer
- J 42737 Sector Bearing Installer
- J 42738 Seal Installer
- J 43484 Seal Installer
- J 44295 Clutch Pack Shimming Kit
- J 45237 Input Shaft Bore Seal Installer
- J 45380 Transfer Case Rear Bushing Remover and Installer
Important: Use only new retaining rings.
1. Install the input bearing.
2. Install the input bearing retaining ring.
3. Install the front output shaft front bearing.
4. Install the front output shaft front bearing retaining ring.
5. Using the J 8092 (1) and the J 36370 (2), install the front output shaft rear bearing.
6. Using the J 42737, install the control actuator lever shaft bearing.
7. Lubricate the control actuator lever shaft bearing.
8. Install the control actuator lever shaft.
9. Install the NEW retaining ring for the control actuator lever shaft. Ensure the retaining ring is fully seated.
10. If it is a new shaft, or if the cup plug was removed, install the cup plug in the front output shaft, using a suitable driver.
11. If removed, install the front output shaft rear bearing race, using a hydraulic press and a suitable driver.
12. Using the J 36373 and a hydraulic press, install the tone wheel on the front output shaft.
13. Install the front output shaft assembly.
14. Install the front output shaft retaining ring.
15. Lubricate the thrust washer for the input shaft with J 36850 or equivalent.
Important: The transfer case may use either a 4 pinion or 6 pinion planetary carrier assembly with the 27 tooth input gear version of the transfer case, transmission RPO M30. If the 6 pinion planetary carrier assembly used with the 27 tooth input gear requires replacement, the service part will be a 4 pinion planetary carrier assembly. The 4 pinion and 6 pinion planetary carriers are interchangeable. The 32 tooth input gear transfer case version used with transmission RPO MT1 and RPO MN8 will still use the 6 pinion planetary carrier assembly.
16. Install the input shaft thrust washer. Align the tabs on the thrust washer with the slots in the planetary carrier.
17. Install the pilot bearing in the input shaft, using the J 8092 (1) and the J 45237 (2).
The bearing installed depth is 33 mm (1.30 inch) from the face of the gear or just below the tapered bore.
18. Install the input shaft assembly.
19. Lubricate the input shaft thrust bearing with J 36850 or equivalent.
20. Install the input shaft thrust bearing.
Important: When installing the input gear thrust bearing washer in the planetary carrier, ensure that the lettering is facing up.
21. Lubricate the input gear thrust bearing washer with J 36850 or equivalent.
22. Install the input gear thrust bearing washer.
23. Install the retaining ring for the planetary gear shaft.
24. Install the planetary gear carrier.
25. Install new shift fork pads, if removed.
26. Install the range shift sleeve in the range fork.
27. Align the range shift sleeve on the planetary carrier.
28. Align the roller on the range fork in the control actuator lever slot.
29. Install the range shift fork.
Important: Install the shift fork shaft in the range fork assembly with the machined hole facing the bottom of the front case half.
30. Install the shift fork shaft.
31. Install the clutch lever.
Notice: Refer to Fastener Notice in Service Precautions.
Important: When performing the following service procedure, ensure that the clutch lever pivot pins are tightened evenly. Ensure that the clutch lever moves freely after the pivot pins are tightened and engaging the lever.
32. Install the clutch lever pivot pins in the front case half.
^ Tighten the clutch lever pivot pins to 40 Nm (30 ft. lbs.).
Important: Ensure that the shift detent plunger is seated correctly on the control actuator lever.
33. Install the shift detent plunger.
34. Install the shift detent spring.
35. Lightly lubricate a NEW shift detent plunger O-ring seal with transfer case fluid.
36. Install the O-ring seal on the shift detent spring bolt.
37. Install the shift detent spring bolt in the front transfer case.
^ Tighten the shift detent spring bolt to 17 Nm (13 ft. lbs.).
Important: The following service procedure is to be performed only if the rear output shaft is new.
38. Install the rear output shaft oil restrictor flush with the end of the shaft.
39. Install the clutch housing bearing, using the of 8092 (1) and the J 36370 (2).
40. Install the clutch housing on the rear output shaft.
41. Install the clutch hub.
Important: The fingers of the clutch hub spring face up.
42. Install the clutch hub spring.
43. Install the clutch backing plate in the clutch housing with the notch in the plate facing down.
44. install a friction clutch pressure plate.
45. Install a steel clutch pressure plate.
46. Continue to install the friction and the steel clutch plates, alternating until 10 friction plates and 9 steel plates are installed.
47. Install the clutch hub retaining ring.
Important: A clutch plate shim package is necessary in order to have the proper shims available for setting the correct clutch pack preload. Improper preload can cause driveability concerns and failure of the transfer case.
48. Securely install the base plate (3) of the J 44295 in a vise with the machined surface of the locating tabs facing up.
49. Install the assembled rear output shaft with the clutch housing, the inner clutch plates, and the outer separator plates on the base plate (3) of the J 44295.
50. Install the weight (1) of the J 44295 on top of the assembled clutch plates.
51. Place the gage block (2) of the J 44295 on one Of the locating tabs of the base plate (3) of the J 44295.
52. Using a feeler gage, measure between the gage block (2) and the weight (1) of the J 44295.
53. Measure with the gage block (2) and the feeler gage on the remaining two locating tabs of the base plate (3).
54. The average of the three measurements is the required shim thickness.
Important: Measure the clutch shims in the center area of the shim. The shims may have a burr or ridge around the inner or outer edge causing an incorrect measurement. The available shims may not combine to the desired measurement.
55. Select from the clutch plate shim package the correct shim or shims plus or minus 0.10 mm (0.004 inch). You may use a combination of two shims to obtain the correct thickness.
The shims in the clutch plate shim package are the following thickness:
^ 0.30 mm (0.12 inch)
^ 0.56 mm (0.022 inch)
^ 0.81 mm (0.032 inch)
^ 1.04 mm (0.041 inch)
^ 1.30 mm (0.051 inch)
^ 1.55 mm (0.061 inch)
^ 1.80 mm (0.071 inch)
^ 2.08 mm (0.081 inch)
56. Remove the weight (1) of the J 44295.
Important: After obtaining the desired thickness of shims, do not remove the clutch plates from the clutch housing. If you remove, and then reinstall the clutch plates, it could change the measurement.
57. Install the shim or shims.
58. Using a suitable press plate and a hydraulic press, press the clutch pressure plate bearing hub in the clutch pressure plate bearing. Ensure the bearing inner bearing race is supported.
59. Install the clutch pressure plate bearing and hub in the clutch pressure plate.
60. Install the clutch pressure plate spring.
61. Align the tabs on the clutch pressure plate with the grooves in the clutch hub and install the Clutch pressure plate assembly. Ensure the spring is installed in the groove of the pressure plate.
62. Install the clutch pressure plate retaining ring. Push down on the pressure plate to access the retaining ring groove.
63. Align the tab on the clutch pressure plate bearing hub with the clutch lever.
64. Align the rear output shaft teeth to the planetary carrier and range sleeve teeth.
65. Install the rear output shaft assembly.
Important: Ensure to align the marks of the drive chain and sprockets if reusing the chain and sprockets.
66. Install the drive chain and sprockets.
67. Install the drive sprocket retaining ring.
68. Install the driven sprocket retaining ring.
69. Install the oil pump seal.
70. Install the rear output shaft retaining ring.
71. Install a new oil pump O-ring for the oil pump suction pipe in the oil pump.
72. Install the oil pump assembly.
73. Install the oil pump screen.
74. Install the connector on the oil pump screen.
75. Install the oil pump suction pipe to the oil pump.
76. Connect the oil pump suction pipe to the connector.
77. Install the transfer case magnet.
78. Install the rear output shaft speed sensor reluctor wheel.
79. Install the speed sensor reluctor wheel retaining ring.
Important: Install the rear output shaft bearing with the groove for the retaining ring facing up.
80. Install the rear output shaft bearing.
81. Install the rear output shaft bearing retaining ring.
82. Align the outside retaining ring for the rear output shaft bearing so that it is easily accessed through the opening in the rear case half.
Important: Ensure that both the sealing surfaces on 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.
83. Install the locating pins in the front case, if necessary.
84. Apply a 3.175 mm (1/8 inch) bead of RTV Sealant GM P/N United States 12345739, GM P/N Canada 10953541, or equivalent, to the mating surfaces of the front case half.
85. Lower the rear case half in to place.
86. Using a pair of snap ring pliers, open the retaining ring for the rear output shaft bearing,
87. Push down on the rear case half until the retaining ring is properly seated on the rear output shaft bearing.
Notice: This component is made of magnesium and proper assembly is required to prevent damage. Ensure the magnesium transfer case housings are properly insulated from all external steel components or galvanic corrosion will occur. New nylon coated case bolts and aluminum washers must be used. Use only aluminum fill and drain plugs. Use only aluminum brackets under the case bolts. Ensure new seals are installed that have a rubber insulated outside diameter and have no tears or cuts. Extensive damage will occur if there is galvanic corrosion between the magnesium and steel components.
88. Install the new case bolts, washers, and brackets.
^ Tighten the case bolts to 37 Nm (27 ft. lbs.).
89. Install the access hole plug.
90. If removed, install the transfer case mounting studs to the height of 29.5 mm - 30.5 mm (1.16 - 1.20 inch).
91. Install the rear vehicle speed sensors.
^ Tighten the speed sensor to 15 Nm (11 ft. lbs.).
92. Install the front vehicle speed sensor.
^ Tighten the speed sensor to 15 Nm (11 ft. lbs.).
93. Install the actuator insulator to the transfer case.
94. Install the encoder motor to the transfer case. Rotate the control actuator lever shaft to align to the encoder motor.
95. Install the mounting bolts for the encoder motor.
^ Tighten the encoder motor mounting bolts, in the sequence shown, to 20 Nm (15 ft. lbs.).
96. Install a new rear output shaft bushing, using the J 45380.
96.1. Install the bushing or the finger section of the J 45380.
96.2. Install the finger section to the main body of the J 45380.
96.3. Position the bushing and tool to the case.
96.4. Using a hammer and the J 45380, install the bushing.
97. Align the rear output shaft seal to the rear case, with the square tab up and the drain hole down.
98. Using the J 37668-A, install the rear output shaft seal.
99. Using the J 43484 (2) and the J 8092 (1), install the front output shaft seal.
100. Using the J 42738, install the front input shaft seal.