9kI4

I've got a vibration at speeds of 75-85 that I can't pinpoint... Help me please!
It's a 2002 that I got last May with 19k on it. It had SO3's at the time and never had any problems. Now it's got 41k on it with Kuhmo MX's on the rear, still the same SO3's on the front. I got the tires through mail order and had them mounted on the stock rims at a local Just Tires. They seemed to be fine through the first couple months but in the last couple months I've noticed a lot of vibration coming from the rear. It only occurs at about 75-85, constant speed. It doesn't seem to change with accel/decel. I thought it was a wheel balance problem so I took it back to the same place and had them rebalance all four corners. I'm fairly sure it is not a problem at the front of the car because the steering wheel is rock steady. It really just feels like it is coming from the back of the car. It shakes through the seat and now I've got rattles everywhere. The car shakes so bad you can feel your teeth chatter. There is no noise that goes with this, just shaking.

Bad tires? The tires actually felt like they were flat spotted on a couple of really cold mornings this winter, and the car is not garaged so could that be an issue? Could the tires have flat spotted, so to speak? Could it just be a bad set of tires.

Any help would be great. I guess I'm probably going to have to take it to service, I just can't stand to think of leaving the car at a dealer for days or weeks to figure out problems.

9kI4

One more thing...
The vibration isn't constant. It comes and goes and I can't figure out any reason or pattern to it.

9kI4

Oh yeah!
When I go over a bump, like a speed bump, at very low speed I hear some kind of squeaking coming from the front. Sounds like the front right side. Any ideas on this? Could they be related?

Slows2k

There are few possibilities. Bad tires, bent wheel, badly worn inner CV joints. since the vibration came with the tires, they are the primary suspect. I'd have the tires rebalanced, and check the inner joints for wear. See if you can borrow another set of rear tires from a local owner for a quick drive.

Kumho's have been known to be vibration prone.

9kI4

I've already had them rebalanced once to no avail. If it was a bent wheel wouldn't I be able to visually inspect the wheel and see damage. What other things should I look for as far as the CV joints. I don't hear any noises coming from the rear.

9kI4

Any other help?

Slows2k

Has anything new been done to the car?

C6400hp

I still suspect it is a wheel balance issue. I know you took it back to the same place but, I would take it in again to someone else.Maybe someone who is experienced with high end cars. If it only happens at speeds of 75-85 and on a car with such mileage, wheel balancing is almost what it has to be. Are the weights on your wheels on the inside or outside edges of the rim? They should be stuck to the center of the wheel.Has your shops machine been calibrated lately.As little as 1 gram off can cause vibration at that speed.

BroInTheKnow

Vibration at high speeds could result in bad CV joints or a bad u-joints in your driveshaft. if your car has 41k miles on it then it just might be the tires. I would recommend the Toyo Proxees 4 which I just installed on my car and the ride is awesome.

There is a benefit when your dad owns his own shop =D

Slows2k

Sorry, no u-joints in the driveshaft.