[BLUE427]

Bart, I had the same problem with my spf , 2585. I originally had the factory Eagle gt II's on the 15 inch rims and all was fine.I then replaced them with pse 17" and michelin 275's in the front and 335's in the rear. Then I gained a vibration at the 65-70 range, if I accelerate past that point , it goes away. Sounds like the same condition as you have. I know the allignment and everything else is fine, as it did not shake with the factory ones on it. I am going to road force balance them soon, and if that doesnt help, just deal with it I guess. good luck,
Marty