I have a driving noise which only manifests at 40 to 45 MPH. This noise is like a viabration noise from a rough or wash board road. It slowly changes pitch and intensity. The car has pretty new tires, the car has just been aligned and had the front bushings replaced. The car had the complete drive shaft replaced prior to my purchase of the car. Haven't checked wheels and balance yet, but wanted to know if anyone had any ideas besides that? Could body bushings cause this kind of problem like on the E28's? This car has 108k miles on it.