Transfer Case Growl or Grinding Noise

WARNING: This page is about a different car, the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Chevrolet Tahoe, 2007 Chevrolet Suburban, and 2007 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

Cause	Correction
DEFINITION: A faulty internal transfer case component that causes a growl or grinding noise in the transfer case while the vehicle is turning or in a four wheel drive mode. Review the Symptoms - Transfer Case and perform the necessary inspections.
High/low planetary carrier assembly	Inspect the high/low planetary carrier pinion gears for the following conditions: Chipped, bent or deformed teeth Pinion gear needle bearings worn Pinion gear thrust washers missing Seized or binding pinion gears Refer to Cleaning and Inspection . Replace the high/low planetary carrier assembly if any of the above conditions exist. Refer to Transfer Case Disassemble and Transfer Case Assemble .
Annulus gear	Inspect the annulus gear for teeth damage or wear. Refer to Cleaning and Inspection . Replace the front case half if the annulus gear is faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble .
Input gear	Inspect the input gear in the planetary carrier assembly for excessive thrust end play. Refer to Cleaning and Inspection . Inspect the input gear teeth for the following conditions: Gear tooth failure Worn or galled thrust surfaces Refer to Cleaning and Inspection . Replace the input gear if faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble .
Thrust washers	Inspect the thrust washers for being broken or missing. Inspect the thrust washers for galling. Replace the thrust washers if faulty and the mating component if damaged. Refer to Transfer Case Disassemble and Transfer Case Assemble .