Haven't driven my 185K mile, 2006 H3 in awhile (kids car). Took it out yesterday and noticed a very subtle vibration in the gas pedal - not the steering wheel - at 25MPH and above. Most noticeable when accelerating and cruising. Totally consistent, always there. It sure feels to me like it's coming from the drive train/center of the truck.

At 40 MPH I put the trans in neutral and revved the motor a few times - vibration not coming from there. Also when I put my fingers on the (auto) shift shaft, inside the boot - nothing noticeable there, either. It's a very fine, subtle vibration - like if I put a big bracelet on a propeller shaft - almost a tinny feeling/sound. Like a thin, light, heat loose heat shield - but not as obvious. Have I made my point yet ?

I suspect U-Joints. When D and R in the driveway - sounds like a ton of slop. I am away from the truck but next step is to get under and try and twist driveshaft back and forth - how much play is too much? There is no clicking or bumping at low speeds. Car stops straight and true.

Any other ideas or thoughts appreciated!

 

When was the last tire rotation? What does the wear look like?

U Joints clunk in and out of drive/reverse, it's what they do. It is a matter of degree.

When they squeak and/or chirp, that's a problem.

 

Hey forgot I never follow through on this post.

I jacked the frame and found the wheel a bit wobbly in all directions - so it was the wheel hub that went bad.

Replaced it with $195 . Man, the prices for those things are all over the map! Was so tempted to try the cheapest one, but didn't want to do this job twice. Also followed popular YouTube advice and used power steering, socket extension wedged against control arm and lots of PB Blaster to PRESS on the (3) loosened wheel hub mounting bolts to get the hub off - after 180K miles and new england sand/snow, that hub was FUSED to the spindle!

All well now. Thanks for the help!