When I put the 4x4 on I heard a clunk then it wouldn't dr...


When I put the 4x4 on I heard a clunk then it wouldn't drive, it will drive when it's in 2 high Mechanic's Assistant: What is the make/model/year of your car? 2002 Chevy Avalanche Mechanic's Assistant: Are you fix...

When I put the 4x4 on I heard a clunk then it wouldn't drive, it will drive when it's in 2 high Mechanic's Assistant: What is the make/model/year of your car? 2002 Chevy Avalanche Mechanic's Assistant: Are you fixing your vehicle yourself? What have you tried so far? I haven't tried anything yet Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you? That's it

Automotive Expert
Hi there, I am Cam. I am licensed automotive technician with more than 20 years experience. I will be happy to assist you today. 

The website will automatically offer a phone call, you do not need to accept that offer. 

I am sorry to hear you are having issues with your Avalanche, I will help you. 
 
May I please get your name while I look over your question?

Chris
Automotive Expert
Chris, this sounds like there may be a problem in the transfer case. have you looked at th condition of the transfer case fluid?

No I haven'tWill I wreck it driving it it two wheel to the shop?
Automotive Expert
That is where I would go next. I suspect you will find anything but clean blue fluid. The clunking, the loss of drive when in 4wd suggests there is a fault due to worn out parts. I fear the damage is done, but no it should not do anything more by driving it to the shop.

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