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Thump noise while turning


Full Member
Jul 2, 2004
Farmers Branch, TX
I am trying to pin-point when it is happening, but it seems when I make a left turn there is a thumping noise coming from what feels like the driver's floor pan.  Not sure if it does it while I am turning and braking. 

Anyone have this happen?
I'm having the same issue.  Taking mine back in any day to get it looked at.  Truly annoying..  Its like when I come to a turn really fast and make a right or left turn I get what sounds like joints popping and I feel it under my feet.  Won't stand for it...
I have the same issue.  Took it to my dealer 3 times and the problem was finally figured out.  There is a body panel mounting bolt that is slightly too long.  They shimmed the collar on the bolt and it went away.  Have them check for it.  Good luck!
Can you identify which bolt it might be?  I've been to my dealer twice and still can't find anything, but I can't take it.  Its driving me insane.  I looked under my floor pan, but don't have any idea where to look.  Thanks!! 
Sorry for the long reply, I recently moved to virginia and do not have access to the service records concerning the fix.  My dealer dropped it off to my office and the thump was gone.  I did not ask any more specific questions, I was just happy it was fixed.  sorry guys...

I get that problem too.  Mainly when I am turning left on an incline.  I told the service dept where it happens at, (which incline), and of course they could "not duplicate" the problem.
Yep.  i have the same issue.  I haven't taken it to the dealer yet.  I would rather find the problem and then tell them what to fix.  I don't want to have to go back & forth 3 times.

Hopefully someone will figure it out!
I took my AV in today for a rattle problem and mentioned the pop/thump as well. Went on a little drive and the service manager and the gm factory rep with me both heard it, so hopefully they will get it figured out. I will let you all know what I find out.
Mines in the dealership now getting worked on.  They ordered a cushion....  Anyone know what that is.  They haven't told me the problem just said they ordered a cushion...  We'll see if that fixes the problem.  Will report back when I get my AVA back.
When I got mine back they didn't do anything for the thump noise, wasn't on the service write up. I will have to take it back in one of these days. I am too busy right now and I have a pregnant wife that is due any minute now.
Yeah, I still have not had time to take it to the dealer either.  I am hoping to take it this week for a couple of TSBs too.  Will post if I get an answer and a fix.
chemanfit said:
When I got mine back they didn't do anything for the thump noise, wasn't on the service write up. I will have to take it back in one of these days. I am too busy right now and I have a pregnant wife that is due any minute now.

Thanks!  Congratulations on the little one!
dang i figured gm could have fixed this its most likekly a body bushing thats what waz wrong with my 05  :E:
OK, just took mine in today.  So far, no thumping.  On the service invoice it has part # 15899719, description: insulator, qty:4.

still from invoice:  Sounds like a thump sound movement/ popping in position #2 body mounts R&R pos 2 mounts noted witness marks.  Installed nylon insulators (2) to both sides.  Lowered body and retorqed mounting to specs e1104 .9 / e1103 .7.

First part makes more sense to me, second doesn't.  But I figured if that is tech lingo, then I will include it.
One other possibility, while looking underneath my 2007 with just 4000 miles on it, I noticed the passenger side sway bar mount was completely loose!  The long bolt which bolts the end of the bar to the chassis had backed out and had about two threads left connecting it!  The rubber bushings were not even in contact with the metal mating surfaces, it was so loose.  Although I wasn't getting a thumping noise yet, I've had this problem before on other vehicles when the sway bar connections aren't sound.  Also just found the dreaded engine oil leak on the lower part of where the block meets the transmission bell housing... also lost a trim bolt form the side step rail, others were all loose....off to the dealer we go....
First, I love the Alvanche!

My 2007 with 4900 miles on it, also has a noise (more of a clunk), when the truck is going in and out of dips or certain bumps.? The noise happens more when it is at an angle (lower dips, up and down hills).

The dealership replaced one left front shock and spring.? The noise is still there.
(Dealership is throwing parts at the problem)? (n)

After reading mike socal message, I'll look under my front end to see if there is any loose bolts.

VRF201 (Roy)