Hey guyz,
I have a 2009 Hummer H3 3.7ltr, currently on 210k kms. Issue with my hummer is when driving at the particular elevation on highway at a speed of 110 kmph I get a clunking sound from under my handrest, looks like the sound is coming from the transfer case. so I showed it to a mechanic who is specialized in hummer repairs and all but he was unable to rectify the issue. Things what he had done are as below.
1. removed the transfer case and replaces with a refurbished one - (after that test driven and still the problem continued to show)
2. removed and dissembled the transmission and rebuild it - (found no issue with it)
3. replaced the front drive shaft as it showed signs of wear out .
4. checked the rear differential to see if there were any worn out teeth's, but could not find any.
After all this he couldn't solve the issue.
Eagerly waiting for your advise..

 

Does your A$$ hurt? Check the front diff bushings.

 

Will check that too ..

 

Never a good idea to throw parts at a problem until you actually diagnose what it is so it can be fixed.

Definitely LOOK at the front differential bushings, there are three, they rot, crack and allow excessive movement.

 

"...a mechanic who is specialized in hummer repairs..."

Yeah, doubtful. More like "specialized in making people's wallets lighter".

 

Well the place where I live they aren't any good mechanics to look into the matter as I said before many of them looked into it and could not find the issue. I will look into the front differential bushings as you said but I would like what are the symptoms of a bad front differential bushing as recently I had replaced the upper and lower arm bushings as it was worn out..

 

Principal trained and certified mechanics and technicians who keep up-to-date with the latest developments are employed. Factory training programs are held on the premises regularly.

 

could you please show me the pictures of the bush located as you had mentioned.

 

You are obviously on the internet, but oblivious to how to do a GOOGLE search?


GOOGLE: H3 Front Differential Bushings and LOOK at all the images that come up.

 

Thanks for the info..
would like to let you know the mentioned bush is in good state..also I had test driven with the front drive shaft disconnected with 4hi locked and loaded the SUV with passengers.But the same clunking sound is still there.
On straight it does not make the sound..
it happens only when driving above 100 kmph on elevated highways (high or low slopes)
or when driving in graded roads