2002 Cadillac Escalade Ext

Drive Train Axles Bearings problem
2002 Cadillac Escalade Ext V8 All Wheel Drive Automatic 150000 miles

1. Seems Transmission/front axel or Transfer case has made a hum for a long time. In fact Transfer case oil has been silver for many years. That said
2. A banging or thumping is heard under medium and heavy acceleration. When maintaining operating speeds (gas pedal applied) thumping stops and a vibration or ratcheting noise is heard. I do not want to just assume the Transfer case is bad because I have seen contaminated oil, so wonder what the cause may be. No issues in a turn. No banging when shifting gears
May 10, 2010.

2002-2005 K-trucks were pretty common for having an issue in the front axle where the left side bearing adjuster locking tab would break. The adjuster would eventually move altering front axle backlash and preload setting. You can pull the front diff drain plug and check the magnet for metal. A little is normal, excessive amount is indication of a problem. Through the years, I have seen as little as scored bearings, to a couple occasions where the axle had seized. This is just food for thought, and would relate more to a humming/growling noise, more than a banging or thumping. It all depends on the severity. You say the transfer case fluid has been silver for many years, was this known and never addressed by servicing, or has it been serviced and returns to a metallic state? Is there any kind of hesitation, or feeling when this occurs?

May 11, 2010.
1. The left side bearing adjuster sounds like it could be problem at least the banging sound seems to come from in front of and on the left side of the driver. Today I tried being in drive with foot on brake and depress the gas while staying in place the banging occurred. What is the fix? What is best way to check?

May 12, 2010.
If you can duplicate it with a torque brake, the bearing adjuster would not be a possibility. Do you have an issue with the front axle, it is highly probable. If you can duplicate it stationary, then a second person either running the truck, or determining where the noise originates from, would be the best option. Nothing comes to mind on what the cause could be, without being able to hear it.

May 14, 2010.