My 2006 hummer h3 with nearly 72k miles has developed a weird issue:

After the vehicle has sat for atleast 8 hours, when I start her up and drive I feel a clunking at the back right tire. It's like the tire is warped/uneven. The vehicle physically bumps-bumps-bumps as i leave my driveway and head down the street. As I pick up speed (25MPH) the clunking/bumping disappears and returns to normal.

Is this a bad wheel bearing/hub? Has anyone ever experienced this before?

I had all my tires rotated and balanced, they are all "fine". I inspected my suspension and everything looks ok. Anyone help/advice would be appreciated.

 

Just a shot in the dark here, but if you use the parking brake perhaps the brakes on that tire are sticking a little after being engaged for a while?

 

Thanks for the input, I'll engage the parking brake a few times and keep it off a few times, see if there's a difference.

Honestly I barely use the parking brake so I figured that couldn't be the issue.

 

Tires flat spot after sitting, you notice it more as the tires age and wear, and when it is colder temps. It is also worse when under-inflated. Once you get rolling they heat up and the flat spot disappears until the next time you park it.

When was the last time tire PSI was checked?

 

I checked them within the week, all appeared to be within normal range (35psi) but the tires are a less common brand. I hope it's the tires, as that is much less costly than hubs or suspension problems.

 

What's interesting is that I rotated the tires, had them aligned and balanced , and the problem is still near the back passenger side. Leaf springs and shocks looked fine the other day when I inspected them. Such a weird ordeal

 

I had a clunking noise coming from the passenger side rear, couldn't really tell if it was under the truck or not. After about a week of listening to it and many forum searches. I found It was the rear door bottom latch support mechanism. The part below the latch that sits on the door jam that needed to be adjusted. A temporary fix was to wrap 5 or 6 loops of electrical tape around this metal 'V" plate (on the truck side) to snug it up where it mates into the "female" side on the door. May not be your issue, but worth a try.

 

Is this what your talking about ?