Went to 20s and need help

[mrcohlmia]

I don't know if anyone will look at this thread again, but I am having serious vibration issues. I have had my replica 20's with michelin diamaris tires for about a year now. When I first got them I did not notice any vibration, but my problems as of late have been many. At 55 mph the steering wheel shakes visibly, like the front wheels are moving from side to side or something. Outside of that speed that does not occur. When I brake the stearing wheel shudders similarly but for only a second, like a disc is warped or something. My main issue is this. Because I travel long distance a lot I notice this. From 70 mph to 90 mph the car vibrates constantly and passengers notice it, and more importanly it drives me CRAZY!! I have had the wheels balanced many times at different places and I have the same problems. Alignment is not the issue either. BMW says my control arm bushings are worn down or something, but they also tell me this would not fix any of my problems except the shuddering of the steering wheel when on the brakes. I don't know what to do now. Do you think inflation over 32psi would cause vibration at highway speeds?