I have a 2007 Mazdaspeed6 with 6700 miles. the rear left is almost bald & the right rear is not much better. It's AWD and I don't squeal the tires etc...The dealer says they examined the car (I don't know how well in ten mins). ANYhow... I'm stumped as to what is causing this excessive wear. Could it be something wrong with the traction control????? HELP(cheers2)