The Penny Test: Measuring Tire Tread Depth
The penny test is a simple exercise that you can perform on your own tires. It will tell you if the tread is too low and needs to be replaced. Keep reading to find out what we mean by the "penny test" and how simple it is for you to measure your own existing tire tread levels.
When to Replace Your Tires
No matter what type of tires you're driving on — winter (or snow) tires, all-season tires or summer tires — if the tread is worn and bald, your safety and traction are drastically impacted. Tread helps your tires grip the road and helps your vehicle respond quicker in adverse weather conditions, such as rain, snow and ice.
Be sure to check your tire's tread regularly and to replace your tires if the tread has been worn down to 2/32". When your tread gets this low, replacing your tires isn't really an option — it's a legal requirement. By law, your tires are considered to be unsafe for driving when they reach that 2/32" level.
How to Use the Penny Test to Measure Tire Tread
Have a feeling that your tire tread may be dangerously low? Think that your tires might be borderline bald? Then dig deep into your pockets, your couch cushions or your piggy bank, grab a penny, and head out to your garage. It's time for the penny test.
To effectively measure tire tread depth, you first need to know how to position the coin. Place a penny with Lincoln's head upside down and facing you into the shallowest groove on the tire. Here's a good rhyming memory aid for you to use when trying to remember how the penny test works: Head into the tread.
Now that your penny is in your tire tread, what do you see? Can you see Lincoln's chin and nose? Perhaps you can see his chin, nose and eyes? If so, that's great — but if you can also see the top of Lincoln's head, then this means your tire treads are too shallow and worn. If the tip-top of his head is at all visible, then it's a sign that you have 2/32" or less of tire tread remaining, the magic fraction that, by law, requires you to get a new set of tires.
Think of the penny test as an alternative to a ruler to gauge or measure tread depth. And be sure to check multiple grooves — inner, outer and central. Depending on how often you rotate your tires, certain areas of your tires may wear faster than others.