Notice that you are from the Baltimore area. Do you have any recommendations on reputable MB tech I can use? I have been taking my car to Benson in Annapolis, but they charge $69 per hour for labor. What bothers me most is the dealer insists that I should not worry about it since I have double row of chains. But then again my car is still under warrenty, so in case the chains do go, its not $$$ out of my pocket. BTW, I have 64K miles on mine.