Just changed my two rear tires (michelin) on my '99XC. The guy said that since I have goodyears on my front, it would cause long-term damage to my AWD system. Nowhere in my owners manual states this. Only if the tire dimensions are different could it be a potential problem, which is not my case. In fact my dealer changed the front tires from the original, and said no problem with it. Comments?<P><BR>Has anyone notice a sort of subtle shaking when accelerating from stop?