Hi CmmE3289, you mentioned vibrations, I presume you had or did work on new sway bars, control arms, have you had the car wheels re-aligned? since any alterations have been done? When you rotated your wheels, I guess you put your rotated, your front wheel to rear and rear to front? with this you may have a problem here just doing this. After I bought and had new tyre/s ballanced before fitting on vehicle (bmw 735), and told not to alternate wheels as I described, as the new rear wheels tyres as fitted were (although new) were not suitable to be on front? Just some information from a tyre shop here? hope this helps.