My vehicle is brand new; its not even at 5000 miles yet.
Every time i'm driving at slow speed, and after at least 15 minutes of driving, a clamping noise comes up.
It sounds as if a small metal box is inside a slightly bigger one and the smaller box keeps banging against the bigger box.
I can hear something clamping or banging under the vehicle. I also feel the clamp or banging on the gas pedal, when i rest my foot on it, and on the brake pad ,when i'm about to come to a stop.
Hummer service first told me that they could not pin point the problem. Then they said that this is common on all H3Xs.

 

this might help you out. https://www.hummerforums.com/m_67824/tm.htm

They say it's common on all H3Xs? So did they share anything about it? H3X isn't different mechanically than a standard H3.

 

Most 07 H3's have that problem. I heard and feltit right when I left the dealership!

 

If it is so common how come no one knows what it is? And what is different about the 06 H3 that it does not have "what most 07's " have?

 

I believe the 06 had it's share of problems.

 

You may have figured this out altready, but we do know what it is. A steering shaft defect. alrock posteda link to the threadabove.
That thread has been at the top for awhile. It amazes me that no one looks there first.
And yes, some are starting to report the same issue on '06 H3'sas well.

 

No such noises from my '07 H3X. It's a very tight and quiet ride.

 

kinky

 

THERE ARE TWO ANSWERS!!!!
I cut and pasted answer number 1from a member at another website, who sent me the message.

Answer numbre 1-
Subject: Clunk Or Knock Noise Heard And Felt Through The Steering Wheel Or Brake And Accelerator Pedals - keywords intermediate rattle shaft #PIT4448 - (06/27/2007)
Models: 2007 Hummer H3
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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A clunk or knock noise is heard and felt through the steering wheel or brake and accelerator pedals, the cause is a slip/stick condition in the lower steering shaft. This is a temperature sensitive issue and usually requires the vehicle to have been driven for a period of time to increase under hood temperatures

Recommendation/Instructions:
Replace the lower steering shaft part no. 25776339. There is a high probability that replacing the shaft will correct the condition as there are only a small percentage of parts that exhibit this condition. This PI will be updated when a new part number becomes available.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
__________________________________________________ __________


Yet another member wrote thatthe biggest problem here is that the part has yet to be redesigned, so most likely the problem will comeback.


answer number 2-
Igot this answerfrom yet another member who stated that:
Several owners have already changed the shaft. However, the problem continues, and that least one owner has reported to have been told by mechanics that this is related to temperature sensors and to have thne also changed.

don't know about that , but the person who posted the original answer number 1says in his post, cut and pasted above, that this is a temperature sensitive issue. So this guy may be right

 

We are all very happy for you[sm=smiley22.gif]....

Try taking it off roadto loosen things up a little