While you are checking the air pressure on each tire, visually inspect the tire's tread and sidewall for signs of wear and road debris that may have penetrated your tire.
Tires depend on good tread condition to maintain traction and to shed water on wet roads.
Tread depth should be checked for excessive and uneven wear. Although it is not as accurate, you also can check tread depth by placing a penny in the tread of the tire. If President Lincoln's entire head is showing, it is time to replace your tires. The more tread the tire has remaining, the higher the reading will be. Uneven readings indicate improper tire inflation or the need for a wheel alignment.