Steering Wheel Vibration

I have a '90 SC that I've owned since 16,000 miles. I've ALWAYS had trouble with what seems like tire inbalance ....... I get this annoying vibration in the steering wheel. I can improve it by having the wheels spun on the car after a good dynamic balance but can never totally cure it. I've installed new front struts and bushings but the problem persists. Am considering a new rack. Is this a common SC problem? Any cure? Tires are Goodyear 225/60 RSA's.

I know that thunderbirds are sensitive to....

Vibrations!

Anyway, Balancing, Tire inflation pressure, and alingnment are all critical. One little thing out of place and you start to feel vibes on the highway.

Have your tires "Road Force varience balanced". The machine is a "Hunter 9000" to do the job right. You might pay a bit more for the service, but the balancing is very good. They match up the high side of a tire (no tire is perfectly round) with the low side of the rim (no rim is perfectly round either).

Make sure you are running the proper tire pressure, this is often overlooked.

Alingment must be set properly.

Also consider new tires. If the tires you have on there vibe too much, they could have worn unevenly and the problem won't get better until you get a set of fresh tires. I had a persistant vibe in my old tires and it was due to a bab belt. I would balance the tires and a week later they would be out of balance again.

Also, when mounting the tires on the car, line the valve stem up with the painted wheel stud. There is supposedly a preset balance in the wheel bearing to compensate for the valve stem. At least that is what I read on TCCOA.