 This is Brad Keselowski, driver of the number two discount tire Ford Fusion. My pit crew uses a lot of sophisticated tools to keep my car in winning shape. But all you need to check your tire's tread is a penny. Simply insert the coin, Lincoln's head first, into your tire groups. If you can see Lincoln's entire head, it's time for new tires. Remember, tires with proper tread stop and handle better, especially when the roads are wet. A message from the U.S. Tire Manufacturers Association.