shudder at 45mph

[Highrisk]

My wife's '06 H3 was one of those that needed a head replacement. About a month after it was changed, we're noticing a very slight shudder at 45mph. It's very light - and we usually have to ask if it was the engine, or uneven pavement. Maybe we're just overly-sensitive to slight vibrations ever since the head problem. We think it's light enough that a dealer service dept would quickly write NTF and return it.

Any ideas what could be causing our issue now? It's completely stock, never wheeled, has no check engine lights.

[ChiHummer3]

Have you had any work done to the wheels/tires? Sounds like might be a tire out of balance.

Might be worth a phone call to the dealership - just to let them know what's happening and see if they have any ideas what it could be. At least that will get it on record that you're having a problem.

[Desert Dan]

Take a look at your tires to see if there is any strange wear of cupping?

Does it change with RPMs or throttle?


does it happen on concrete or asphalt?
In CA many of our concrete freeway expansion joints that cause a bounce at certain speeds but not a shudder?

[Highrisk]

From what I've seen, its independent of the RPM's.
Also - when we decided it had to be real was when driving on a freshly re-surfaced road. It's been acting this way for about two weeks.
When the AC and recirc are on, I've noticed a smell - that I think is antifreeze. Coincidence? Maybe.



Oh, but it gets better. She just called. She's leaving work, and the check engine light and the traction control lights are on. It's displaying
"Traction stabilization reduced power service stabilization system traction fail"

This would be the second time her stabilization system has malfunctioned and required repair. I doubt it is related to the shudder.. but who knows.

[ChiHummer3]

Well....at least now you know it's going to the dealership. Let them figure it out.

Good luck!!!

[Highrisk]

She took it in once before for the post-head-change shudder. They said it was pretty far out of alignment, so they "fixed" it.
Funny, I didn't feel any pulling or other alignment problems before. Why would a new vehicle that's been dealer maintained be out of alignment with 10,000 miles on the clock? The tires aren't cupping, nor do they show any irregular wear patterns.

Regardless... they re-aligned it, and it didn't fix anything. We'll see what the techs say tomorrow.

[Hummer Guy]

[quote=ChiHummer3]Have you had any work done to the wheels/tires? Sounds like might be a tire out of balance.

quote]
x2

Certainly not normal. Best of luck. Let us know the outcome.

[Hmmm2]

Any news from the dealer yet?

[Highrisk]

Originally Posted by Hmmm3

Any news from the dealer yet?

Not really: They were putting it back on the alignment rack late this afternoon. They said a few other people had complained of vibes - after they performed an alignment... so they were going to check it again.

We told them to keep it another day, drive it around and make sure it's gone.

Factory wheels, tires, etc. bone stock lux package.

[scotty1007]

I just bought a 07 H3 Last friday 7-20 noticed bad vibration when driving home on interstate, brought back the next day they said nothing was wrong, Brought back yesterday to have fuel door installed tech took ride with me noticed it right away they said it had two bad tires changed then and still vibrating I drove around 40 miles on different road conditions you can feel significant vibration in steering wheel.
O yea they were supposed to put chrome door handles and mirriors on for 500.00, I got there and they put this crap Putco Crap on their ,The handles and miiriors were supposed to be factory told them if I wanted that crap I could have bought and installed myself for 150.00