There are several ways to check tire tread depth. The first way is to measure tread depth with a tread depth gauge. The second method involves the use of a penny inserted into the grooves of the tread. Tire wear bars are also used on today’s tires as a hands-off visual indication that a tire needs replacement.
Regular tread depth checks are important to ensure that your car’s tires are safe. Excessive wear can result in a loss of traction, especially on wet and slippery roads. Tires are regular wear items and staying on top of their condition not only ensures your safety, but also gives you the opportunity to plan ahead and budget for inevitable tire replacement.
When using a tread depth gauge, tires need to have at least 1/16-in. of tread or more (this is the minimum amount of tread allowed by law). By using a penny as a quick reference, insert the penny into the tread groove with Lincoln’s face showing, but with his head upside-down. If you are able to see all of Lincoln’s head, the tire needs replacement. If you see a wear bar across the width of the tread while facing it, it’s time to replace the tire. Generally, it’s best to replace tires in sets of four. If your car’s tires show signs of abnormal or unequal wear, have this looked into by a professional technician. Excessive wear on both outer edges generally indicates under-inflation. Excessive wear in the center of the tread generally indicates over-inflation. Cupping or dipping of certain tread sections may indicate worn suspension parts or a wheel balance problem. Saw-toothed or feathered tread edges may indicate wheel misalignment. If your car needs alignment or suspension work, have it done before you drive off with a new set of tires. Taking a “big picture” approach to protecting your tire investment will reap many rewards for miles to come.
Information provided courtesy of Car Care