Take Our Tire Test: When, Why, and How to Replace Your Tires

At some point in your future of driving, you will more than likely need to purchase new tires. From making sure that your tire’s tread can grip the road like it should to figuring out how big that tire should be, there’s a lot to know about automotive tires to be able to replace them properly.

Test your knowledge now. Then read on below to learn more.

Where can you find out about the correct size and type for your particular car’s tires?

The best places to look for the proper tire size and type is either the placard located in the left front door or the owner’s manual for your vehicle. As long as you know the exact make, model, and year of your car, RightTurn.com can also help you determine the correct replacement tire options. On the other hand, reading the details off the tires themselves means that you’ll be stuck with the same tires at best, or you may not discover if you’ve already been using the wrong type or size for optimal performance.

When should you replace a tire or set of tires?

The penny test, wherein a visible Abraham Lincoln hairline reads as a ‘fail’ when pressed into the grooves of a tire’s tread, has long been a standard in determining whether to keep or replace a tire. However, that space over Abe’s head is the bare minimum legally, so we recommend using the roomier headroom on the U.S. quarter. Either way, be sure to keep more than a 2/32-inch tread depth to stay legal, and plan to replace your tires at least every six years regardless of wear.

How do you tell how old a tire is?

While all the information on the side of your tire—an area called the sidewall—is important in some way, the Tire Identification Number, or TIN, is the only part that will tell you when it was manufactured. Also called the DOT code, after the Department of Transportation that assigns it, the number’s final four digits let you know the week—out of 52—and abbreviated year when your tire became a tire. For more on all the numbers and codes listed in the answers, though, do take a gander at the related article in the RightTurn Tire Guide (link to article on how to read sidewall markings).


One way in which you may try to avoid ever buying new tires is if you lease all your cars short term. Dealers will typically check on your tires for you during any scheduled maintenance, such as regular oil changes. Nevertheless, it doesn’t hurt to keep an eye on your tires anyway—just in case!