07 M8 (stock) is making a humming noise as I accelerate, I can feel it in my feet also. At about 30-35 it starts to wind up like it is time to shift but it doesn't. When I get off the throttle, it decelerates like it would if I was at a slow speed. It has a new belt (250 miles or so) and doesn't appear to be worn. I grabbed the diamond drive and tried to rotate it and it has a lot of play, like 2 0r 3" both directions. Should it have any movement or play like that at all? I need a little direction and insight if possible. Thank you.
