I have had the problem since 94, the daler worked on it to reduce it by changing a lot of things. My dealer and a lot of people in the know tell me it is the car (92-94) I recently have been told to change the lower front bushings, and to get rid of the Michelins because they develop flat spots when sitting> the tires are probably the culprits if the vibration goes away after while. One of these days I might have the bushings changed, the motor mounts, rotors had no effect. The best result ever was to balance the tires, mount them on the car and then add more weight when spinning them on the car. There are not too many dealers that have the equipment, mine in the Chicago area did. I have ben told you could balance a brick, but will it be round