All of you are correct. Tire balance, bad struts (causes feathering on the inside or outside of tire like a ripple as you move your hand arund the tire) bad bearings and suspension arm bushings can cause shake. Trouble shoot and do the fairly simple stuff first ie repack your bearings (every 30,000 miles) have your wheels re balanced and check you struts for damage/wear. Have a reputable shop check your suspension bushings if need be. You've got your ideas now fix the problem. My guess is that it's a wheel balance issue. Good luck.
Henry
Henry
