NP1 NP2 Transfer Case Overheat Insufficient Lubrication - contaminated contamination hi2 hi4 information inoperative lo4 neutral no noise odor oil part performance shift

When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

1. Transfer case inoperative or noisy.
2. Examination of drained oil may indicate overheated/discolored or excessive metal contamination.
3. Disassembly indicates overheated transfer case components.

1. Install mainshaft kit part # 88996610 which includes an updated oil pump assembly to improve oil pump performance.
2. Install new snap rings.
3. Refer to published service procedures.

ADDITIONAL INFORMATION:

The mainshaft kit part # 88996610 contains the following:

1. 12384982: mainshaft
2. 12478084: oil pump assembly
3. 12478087: oil tube
4. 12478088: oil tube o-ring
5. 12478085: oil screen
6. 12478086: connector tube
7. 12478089: tone wheel

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.