Clunk Under Floor During Hard Turns?

[Sundown94]

Hi Everyone!
For the first time ever, tonight on the way home from work I started to feel a clunk through the floor of my 2003 H2 when I make hard left or right turns. It almost seems like something is loose under the truck because if I make a right turn and feel the clunk, it won't happen again during a right turn until AFTER I make a hard left turn (and feel the clunk on the left turn). So it is like when I turn hard left, something slides to the right of the vehicle and then when I turn hard right, it slides back to the left. I can't be positive about what is really going on under the truck, but what I do know is that I can easily feel it through the floor and into my foot (especially my left foot when it is resting flat on the floor in front of the seat while I'm driving). Unfortunately it is also raining heavily tonight (and it is dark), so I am unable to crawl under the truck until tomorrow. In the meantime, does anyone have any ideas on what is clunking -- or thunking or whatedver you want to call it -- under my H2???

Thanks!
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[Agriv8r]

dont know how often i make hard turns, but it there possibly anything in the back of the truck sliding???

[H2R]

Sounds like an axle shaft is gone. I would check them.

[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.
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