Tell you guys what, if I didn't have bad luck I wouldn't have any luck at all. My 06 6-speed is making a nasty noise when it's in 4WD, kind of like hitting a metal trash can with a ball bat, it feels like the trany want's to come up through the floor. I replaced the front drive shaft, that's not the problem. I had a friend lay under the truck and I rocked it under power, transfer case problems. It's quiter than a Christmas mouse when in 2WD. The truck has 89K on it and I don't abuse it. It makes the same noise weather it's in 4 high or 4 low. Any ideas? Thanks in advance.

 

I think you've answered your own question If you're the wrenching type, I'd pop the back off the xfer case and check the chain. The xfer cases that are used are the same as the ones on Range Rovers and the chains are known to just stretch!

They do make a hell of a racket don't they? The entire driveline acts like a giant amplifier. Kinda makes you wonder if you really want your legs that close to all that rotating metal

 

Do I need to pull the trany or can I replace the chain with it still in the truck? Who offers a good chain for a fair price? Thanks again.

 

I'd pull the t-case if I was you. It's pretty easy and it ended up being simpler way of getting the case apart. The snap ring on the output shaft is a real Edit to get off.
I had a popping jerking thing going on with mine. I pulled the back off and replaced the chain but the problem persisted. I ended up pulling it and doing a rebuild. In the end the only thing wrong was a little plastic pad on the end of the shift fork was worn away preventing a positive engagement of the 4wd. So essentially is was going back and forth between 2wd and 4wd as I drove down the road.

 

If you keep driving it it may destroy the case, I saw on a site the damage when chain lets go. The whole case looked like a grenage went off in it.