Guide to Reading Your Tire Sidewall


There are several different parts of your vehicles that you can easily read and decipher to understand more about it. Your fuel gauge and you speedometer are just two of the more obvious examples. However, did you know that you can also read your tire? The letters and numbers etched into you tire’s tread can tell you a lot about the tire itself. Our service team has assembled a guide to reading your tire sidewall.


Tire SidewallTire Class

The first thing you will see on the sidewall of your tires is either the letter LT or P. LT stands for “Light Truck” and “P” for “Passenger car.” Thus the letters represent the class of tire that you are using.

Section Width

Immediately following the tire class, you will find a set of three numbers. These numbers represent the width of your tire in millimeters.

Aspect Ratio

The next set of numbers on your tire’s sidewall is the aspect ratio, which is the sidewall height represented as a percentage of the overall tire width.

Wheel Diameter

The set of numbers following the letter R on your tire is indicative of the diameter of the tire in inches.

Load Range

The final letter listed on the sidewall of your tire will tell you the load range, or how much load the tire is designed to carry. SL indicates 35 psi, while E indicates 80 psi.


Armed with this knowledge, you can now have a better understanding of the tires that help your vehicle get around! If you're still having trouble, feel free to visit our experts in the Morristown Ford Service Department. We're located in Morristown, TN and we're always happy to help!