[Ghines1279]

i know this is not the right area, but i need some knowledge dropped on me and this is where everyone is at. Just drove from miami to baltimore, and i have a crazy vibration in the rear like 90% of the time, when im above 80. (I KNOW THERE IS NO 80MPH Speed limit, i dont need a lecture) New Tires(non run flat), balanced, front and back alignment. I had the rears rebalanced during the trip and the shop i was at said they were balanced fine. so I just kept it under 80. When its up to 100mph and its deceling is when its most noticeable. If i push in the clutch and let RPMS drop to idle its still there. Could it be the tires? How can i check or what do i look for if its the Diff or the wheel hub?

[Guth310]

What type of balancing was performed?

I was told my new tires were balanced and I had the same problem. I searched this topic on the wheel and tire section and found that I got a standard hand balance typical at most shops and not a Road Force balance.

After a Road Force balance with a Hunter GSP9700 all was good. It's recommend as one of the best Road Force balancers.

It's also possible you have a bent rim or what they call out of round tire.

Try that out. Should cost around 20-25 a wheel for a Road Force blanace. Do them all.

[Ghines1279]

thanks, i just looked up both shops that balanced them and neither have this machine. its not constant though. thats the thing, if was a balance issue shouldn't it be all the time, same thing with a bent wheel or an unround tire.

[mad chemist]

Originally Posted by Ghines1279

i know this is not the right area, but i need some knowledge dropped on me and this is where everyone is at. Just drove from miami to baltimore, and i have a crazy vibration in the rear like 90% of the time, when im above 80. (I KNOW THERE IS NO 80MPH Speed limit, i dont need a lecture) New Tires(non run flat), balanced, front and back alignment. I had the rears rebalanced during the trip and the shop i was at said they were balanced fine. so I just kept it under 80. When its up to 100mph and its deceling is when its most noticeable. If i push in the clutch and let RPMS drop to idle its still there. Could it be the tires? How can i check or what do i look for if its the Diff or the wheel hub?

Ghines1279,

Sounds like your tyres are asymmetric (out of round). I had the same problem on my old car (Impreza turbo) and no amount of wheel balancing sorted it. In the end the shop I bought the tyres from replaced them with a more expensive tyre - problem sorted .

Mad.

[marcvtec]

Is this only happening in 6th gear, try in 5th at same speed and see.
If it is only in 6th, something is wrong with the drivesharft/diff/rearend etc.

[Ghines1279]

Originally Posted by marcvtec

Is this only happening in 6th gear, try in 5th at same speed and see.
If it is only in 6th, something is wrong with the drivesharft/diff/rearend etc.

its in every gear, but that still doesnt rule out Drive shaft, diff, or axles. I noticed today that its real bad vibration from 80-110 but over 110 - 120 it seems to be fine. weird.

[Ghines1279]

Update, I marked my tires and rims with a grease pencil, and the rim is moving in tire. It was wet so i couldnt even hook it good, but even in the rain i was able to move the marks about 3 inches from each other. crazy...