Hi everyone, I new here

My 2008 6.2ltr H2 has developed a high frequency vibration sound ( 700-1200rpm ) in the dashbord area. It's driving me crazy. As its most noticeable during low speed starting and stopping in traffic. Engine power and idle all seem normal.

I have changed all engine & trans mounts but no change.
Any help appreciated thx

 

Howdy Reuben, and welcome.

I moved this tech question intro to the H2 section which is where H2 questions go, ..... notice the New Member Sections says Not For Tech Questions.

This is where you will get some answers.

 

I have that same problem. When I reverse or drive forward at a low rpm I could feel a vibration under my feet.
It all happened after I took the H2 for a safety check and came across the mechanic which was a H2 ****
...I tried to see if he tampered with any of the bolts for the transmission mounts and/or engine mounts but they seem to be untouched.

 

Hi Man of War
Did you find the problem?

 

Reuben, I got off tracked from looking for the vibration problem due to high transmission temperature issues and low engine oil pressure.

I replaced the diff oil, transmission oil & transfer case oil thinking It had something to do with the vibration but it's still there.
Hopefully someone on this forum could point us in the right direction.

 

I found my dash rattle in the front passenger door armrest after thinking is was coming from underneath, sounded like u-joints or cv joints or something. Sometimes hard to track those down. You'll have better luck locating it if you can recreate the vibration sitting still. Other wise have a passenger tap on interior plastic while you're driving to see if you can get it to stop even momentarily to eliminate some possibilites... Just sayin Good luck

 

AHH Yes, have a passenger tap on interior plastic while you're driving



IF YOU WEDGE A THIN CARDBORD BETWEEN THE 2 PLASTICS ON THE DASH THE NOISE GOES AWAY.

 

Oh Man! I said have a passenger "tap" on the dash! Lol! Glad you found it, a little super glue should take care of that. Or if you're inclined there are several products and techniques to fix it. But to do it right it needs to come out to be repaired. search "interior plastic weld"

 

thanks everyone
The vibration seems to be consistent with engine rpm and is becoming more pronounced over the past month at around 800-900 RPM.
Have it both in (P/N) & Driving. I'm now thinking something on the engine accessory belt drive or pulley. I still have it with with air-con off.
BTW I have no Hummer / GM Service Center in Macau so any direction appreciated.

 

Blackdragon if you do ever find the problem please let us know. Its been 3 years now and got accustom to it.