My car just had new tires put on the back of car and the back tires were rotated to the front a few weeks ago. Now, I am hearing grinding on the drivers front tire and the steering wheel shakes when coming to a stop. Also, i was rear-ended and had the car in the shop getting a new trunk. Could it be dirt, or a rock stuck? When tires were rotated, they were balanced and aligned and I was told the brakes were still good (they have about another 30,000 - 40,000 miles left) is what I was told. My car is a 2009 cobalt LT and have not had the brakes changed....help!