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For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2009 🢒 H2 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Transfer Case Will Not Shift

Cause

Correction

DEFINITION: While shifting from HI range to LO range, there is gear clashing, no HI range, or the transfer case will not shift from 4HI to 4HI Lock.

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

Shift detent lever
    • Inspect for the following conditions:
      • The shift detent lever at the shift fork cams for being worn
      • The shift detent lever torsion spring for being faulty
      • Refer to Transfer Case Cleaning and Inspection .
    • Replace the following components if found faulty:
      • The shift detent lever cam
      • The shift detent lever spring
      • Refer to Transfer Case Disassemble and Transfer Case Assemble .

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
  2. Replace the following components if found faulty:
    3. • The shift fork pads
    • The shift fork

Range sleeve

  1. Inspect the range sleeve for the following conditions:
    2. • Engagement teeth for burrs or damage
    • Sliding freely on the mainshaft
    • The range sleeve shift fork collar for excessive wear
  2. Replace the range sleeve if it is faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble .

High/low planetary carrier
  1. Inspect the high/low planetary engagement teeth for burrs or damage. Refer to Transfer Case Cleaning and Inspection .
  2. Replace the high/low planetary carrier if it is faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble .

Mainshaft front support bearing
  1. Inspect for the following conditions:
    2. • Failed front mainshaft support bearing in the input gear
    • Journal on the mainshaft for excessive wear or damage
  2. Replace the bearing if it is faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble .
  3. Replace the mainshaft if it is damaged. Refer to Transfer Case Disassemble and Transfer Case Assemble .

Lockup shift assembly
  1. Inspect the lockup shift assembly for the following conditions:
    2. • Shift assembly hub for binding
    • Shift assembly sleeve for damage
    • Burred or damaged engagement teeth
  2. Replace the shift assembly if it is faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble .

Drive sprocket
  1. Inspect for the following conditions:
    2. • Engagement teeth on the drive sprocket for burrs or damage
    • Worn bushing in the drive sprocket
    • Journal on the mainshaft for excessive wear or damage
  2. Replace the drive gear if it is damaged. Refer to Transfer Case Disassemble and Transfer Case Assemble .
  3. Replace the mainshaft if it is damaged. Refer to Transfer Case Disassemble and Transfer Case Assemble .