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Dave Nova
Dave Nova, GMC Technician
Category: GMC
Satisfied Customers: 19450
Experience:  ASE Master Certification. GM World Class Certification
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GMC hummer: what cuases a clunking noise when accelerating

Resolved Question:

what cuases a clunking noise when accelerating in low gears in a hummer h3 2006 model
Submitted: 4 years ago.
Category: GMC
Expert:  Dave Nova replied 4 years ago.

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Is it a single clunk when accelerating?

Customer: replied 4 years ago.

yes its a single clunk, it happens frequently when moving off from a stop line or when i would suddenly accelerate



Expert:  Dave Nova replied 4 years ago.

The common problem with the H2 is the body mount bushings popping. The fix is to install insulators between the body mount bushings and the frame.


Bulletin No.: 07-08-61-006C

Date: July 24, 2008

EI07118 - Underbody Noise, Pop, Creak, Body Mount (Install Upper Body Mount Insulators)

2005-2008 HUMMER H2


This bulletin is being revised to adjust the labor time. Please discard Corporate Bulletin Number 07-08-61-006B (Section 08 - Body and Accessories).


Some customers may comment on a noise coming from the underbody of the vehicle.


This condition may be due to body coning in the area of the upper body mounts.


Install insulators to the upper body mounts.

Customer: replied 4 years ago.

i said that i have a H3 and NOT a H2

Expert:  Dave Nova replied 4 years ago.
Sorry, missed that information. Be right back
Expert:  Dave Nova replied 4 years ago.
On the H3, a clunk when accelerating is normally caused by the driveshaft sticking on the output shaft of the transfer case. The fix is to clean and lubricate the internal splines of the front driveshaft yoke. Use GM Special Lubricant for this.
Customer: replied 4 years ago.


do you think that the front propeller shaft universal joint could be a source of a problem; my mechanic said it is broken and needs replacing

Expert:  Dave Nova replied 4 years ago.

When universal joints break, the driveshaft will fall down on one end. If the driveshaft is not hanging down, the u joint is not completely broken. The u joints can fail and have a good bit of play in them and make a clunk noise. If the u joint is worn, I would definitely address this first.

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