Knocking/Clunk noise

[Thumper8302]

piston slap at least in my case and my dads we both have 01 trucks isnt just one clunk though it continues on for a lil while until the truck is warmed up. at idle its barely noticeable but if you try to drive it too soon then it kinda knocks for a few seconds and goes away

yep mine does the same thing.....

 

[Bertelicious]

My 05 does this too. I was concerned the first couple times but after it continued after every cold start up, I just figured it was normal. Seems like something associated with the A/C. If someone figures it out, let us know.





My 1st Post!!!!!

 

[clean454]

if u guys think its the ac witch it sounds like prolly is
the ac comp comes on with the defroster
so turn everything off ac and defrost do a cold start and see if u hear anything

 

[conservatony]

same here

I just purchased an '07 Yukon and experienced the same problem. One clunk/thud several seconds after start-up... that's it. It sounds like it is coming from under the passenger side. I haven't noticed anything wrong but the noise.