Just curious about this, I don't think it hurts anything but want to be sure.

My Tahoe is a 4dr, 2wd vehicle that is never been off road and rarely has anything in tow. It has about 70,000 miles on it.

The clunck occurs after the truck is turned off and has not been running for about 5 minutes give or take. It is a loud, metallic sound pop. It seems as though this has happened since we bought it new. Dealer does not acknowledge anything is wrong with the truck.

What is this noise?
Is there anything that can be done to prevent the noise (that I can do myself)?
Is this something that will hurt or damage any of the truck?

Sounds like your gas tank popping, it may be releasing the negative pressure that has built up while driving it. I have seen a couple of other posts a few pages back that talk about this problem.

I had a similar sound, turned out to be my muffler.

i have a similar problem, i looked through AF and found what i think may be the answer. i cut and pasted the info i found for your review, please let me know what you find out at your dealer or mechanic, thanks.

What you may be hearing is a driveshaft "clunk" that is caused by the slipyoke sticking to the output shaft.
The problem can be fixed with a new slipyoke from your GM dealer parts. it is a new design just for that concern.
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