Automotive Tire Terminology Explained

Automotive tires are more differentiated now than at any point in history. This is both a good and a bad thing. While it means you have an unprecedented level of involvement in choosing the best tires for you, it can leave many people confounded by the range of terminology used to describe different tires. If you would like to learn more about what such terminology really means, read on. This article will discuss the meanings of three commonly referenced terms.

Tread Depth

Tread depth is a fairly straightforward term. It simply designates the distance between the outer edge of a tire and the deepest tread crevices. Generally speaking, a greater tread depth indicates a tire with a longer lifespan, since it can lose a lot more rubber before reaching a critical point. It is common practice to use measurements of the remaining depth to determine whether a given tire needs to be replaced. Legally speaking, in the United States, a tread depth equal to or less than 2/32" means that your tire must be replaced immediately.

Maximum Load

Maximum load designates the total amount of weight that a given tire can bear. The maximum load is determined based on a particular tire's standard inflation pressure. For light vehicles, the pressure used is generally 35psi. Heavier vehicles—trucks, SUVs, and construction equipment—generally determine maximum load at a psi of 41. Exceeding maximum load represents a significant safety hazard—not just for your tires, but for those inside of the vehicle as well.

P-Metric and Euro-Metric

These are both terms used to designate the size of a particular tire. To learn which type of tire is currently installed on your car, you will need to inspect the string of numerals and letters printed on the side of the tire. If that series is preceded by the letter P, then you can rest assured that you have P-metric tires. No P means that you have Euro-metric tires. You can also check your owner's manual to determine which type should be installed.

In some cases, P-metric and their Euro-metric counterparts can be interchangeable; that said, the best plan is to stick with the last variety installed on your car. That's because the maximum load between the two types of tires is often somewhat different. Generally speaking, P-metric tires will have a lower maximum load compared to an equivalently sized Euro-metric tire. In any case, you should never utilize a combination of P-metric and Euro-metric tires.

For more information, contact local professionals like Discount Tire Centers.