Clunk Under Floor During Hard Turns?

[Sundown94]

Agr thanks for the response. Just to clarify, the hard right and left turns are not tire squeelers, but more like if I am coming up to a left or right turn and the traffic light is about to turn red, so you go a little faster through the turn to make the light. If stop first and then make a slow turn, no clunk. Also, there is nothing inside the vehicle to slide around (because I am so anal about keeping the truck clean and empty).

H2R, thank for your reply as well. Are you serious about an axle shaft going??? Is that common and, more importantly, dangerous???? I have never done any off-roading or done anything that might put extreme pressure on the axles to cause them to fail prematurely. I can say though that I have 80,000 miles of normal local and highway driving. Could it be a CV joint?

Thanks in advance for any additional feedback!!
Sun-

[MattRoberts123]

IMO, this is the SAME problem I and many others on the forum have had. Try going fast from a dead stop and hitting the brakes hard.... does it happen again?

I have taken it to the dealer, and they have told me it is defective body mounts. They have no fix for it and GM doesn't really seem to care to fix it. I am BEYOND furious about the problem in mine, and nothing seems to fix the problem. There are a few posts on this forum about it and quite a few other people have had the same problems. THe only solution that was offered to me by another forum member was to get some silicone spray and spray the body mount areas on all 4 corners of the vehicle.

This did seem to temporarily fix my problem, but it always seems to come back. I hope this helps, and if you find anything else out let me know...

[Sundown94]

Matt, that sounds extremely logical and -- so far -- the most likely cause of the clunk. It's funny that you say body mounts because one of the possibilities that I came up with last night while I was driving was body mounts (maybe the whole cab was moving on the frame), but then I thought "how could that be?". It would also make sense that I felt it for the first time last night because it has been raining hard up here in the Northeast for the whole week and last night was the first time I drove the H2 since Monday (when it was dry out), so the body mounts might have been wet and more prone to "slip". I will see if it stops today or tomorrow now that we have dry weather here. If it does stop "clunking", then I think this comes close to proving that it is the body mounts.

Thanks again, and if anybody else disagrees and/or has any other ideas, I would certainly still welcome them.
Sun-

[mikejr]

Originally Posted by Sundown94

Matt, that sounds extremely logical and -- so far -- the most likely cause of the clunk. It's funny that you say body mounts because one of the possibilities that I came up with last night while I was driving was body mounts (maybe the whole cab was moving on the frame), but then I thought "how could that be?". It would also make sense that I felt it for the first time last night because it has been raining hard up here in the Northeast for the whole week and last night was the first time I drove the H2 since Monday (when it was dry out), so the body mounts might have been wet and more prone to "slip". I will see if it stops today or tomorrow now that we have dry weather here. If it does stop "clunking", then I think this comes close to proving that it is the body mounts.

Thanks again, and if anybody else disagrees and/or has any other ideas, I would certainly still welcome them.
Sun-

I had the same issue in my 2006....dealer couldnt find the source since it was so intermittent. So i fixed it myself and bought a 2008...lets hope i doesnt happen with the new one. I recall someone posting on here that if you torque the body mount bolts a bit it will stop the clunk/creak.

[Vettster]

Had the same thing happen on my 06.
Dealer replaced the right rear body mount and all is well.

[tower]

Do you bowl?

[3Hummer]

sounds like you guys need an H3