GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

DEFINITION: While shifting from HI range to LO range, there is gear clashing or the gear range cannot be selected.

Review the Symptoms - Transfer Case and perform the necessary inspections.

Actuator lever

    • Inspect the actuator lever at the shift fork cam for being worn. Refer to Transfer Case Cleaning and Inspection in Transfer Case - NVG 236-NP8 Unit Repair.
    • Replace the actuator lever if found faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - NVG 236-NP8 Unit Repair.

High/low range shift fork

  1. Inspect the high/low shift fork for the following conditions:
  2. • Worn shift fork pads
    • The roller on the shift fork for wear or damage
    • Cracked or bent shift fork
    • Shift fork springs and brackets for damage
    • Refer to Transfer Case Cleaning and Inspection in Transfer Case - NVG 236-NP8 Unit Repair.
  3. Replace the following components if found faulty:
  4. • Shift fork pads
    • Shift fork
    • Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - NVG 236-NP8 Unit Repair.

Range sleeve

  1. Inspect the range sleeve for the following conditions:
  2. • Engagement teeth for burrs or damage
    • Sliding freely on the rear output shaft
    • The range sleeve shift fork collar for excessive wear
    • Refer to Transfer Case Cleaning and Inspection in Transfer Case - NVG 236-NP8 Unit Repair.
  3. Replace the range sleeve if faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - NVG 236-NP8 Unit Repair.

High/low planetary carrier

  1. Inspect the engagement teeth for burrs or damage. Refer to Transfer Case Cleaning and Inspection in Transfer Case - NVG 236-NP8 Unit Repair.
  2. Replace the high/low planetary if faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - NVG 236-NP8 Unit Repair.

Input shaft pilot bearing

  1. Inspect for the following conditions:
  2. • Failed input shaft pilot bearing
    • Journal on the rear output shaft for excessive wear or damage
    • Refer to Transfer Case Cleaning and Inspection in Transfer Case - NVG 236-NP8 Unit Repair.
  3. Replace the bearing if faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - NVG 236-NP8 Unit Repair.
  4. Replace the rear output shaft if damaged. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - NVG 236-NP8 Unit Repair.