Q: Intermittent vibration caused by shocks & struts?

[pacsoft328]

Hey, I have a 96 Saleen Speedster that just hit 20k miles. I get a small, but nagging intermittent vibration that comes and goes and I feel it in the steering wheel and seat. It seem most noticeable at speeds of 65 to 80. I just had the tires balanced (tech said they were a little off, but not much) and it's better, but still there. I have replaced the BFG Comp TA's with Michelin Pilot Super Sports a couple of years abo, but have not done any other work to the car.

Could the shocks and struts need replacing because of age versus mileage?

Also wondering if I should have the tires road force balanced to see that will fix the problem. Love driving the car, but the vibration on a 500 mile trip gets a bit old.

Anybody's thoughts on this?