How to Do the Tire Tread Penny Test

For years, car owners have been using the "penny trick" to figure out when they need new tires. If you learn this trick, you'll never have to rely on auto mechanics with questionable motives to tell you when you need new tires again.

To conduct the tire wear penny test, simply hold a Lincoln penny between your thumb and forefinger and put Abe Lincoln's head into one of the lowest points on a tire's tread. If the tread covers any of Lincoln's head, you've got good tires. As soon as you start to see the space above his head, however, you'll know it's time to get new tires to keep your family safe on the road. Take a few minutes to conduct this test on various spots on all four tires because different tires wear out at different rates and in different patterns. The tire tread penny test works because Lincoln's head is 1/16 of an inch below the top of a penny, the minimum amount of tread recommended by mechanics. In many states, this is also the minimum amount of tread legal to drive on. If even one tire's tread gets below 1/16 of an inch, the car loses valuable traction with the road and is much more prone to accidents. To keep your tire's tread from wearing below 1/16 of an inch faster than it should, rotate your tires every 5,000 to 7,000 miles.

As long as you're keeping a penny handy to check tire thread, you should also carry a tire pressure gauge. Keeping tires inflated to the right pressure will help you prevent tire failure and save money by improving fuel efficiency. Visually inspect tires every time you pump gas and check tire pressure and tread wear every couple months, especially during the winter when air pressure is lowest. Armed with only a penny and a tire gauge, you can enjoy the peace of mind that comes from knowing your tires are in excellent condition.