Tire Buying Guide

Tire Sizes & Ratings

Before purchasing any tire, you need to be sure you’re getting the right size and type for your specific vehicle. Knowing how to find this important info and what it means will help you make the right call.

Before purchasing any tire, you need to be sure you’re getting the right size and type for your specific vehicle.

Where can I find my tire size?Where can I find my tire size?

The tire size for your vehicle can be found in two places:

Sidewall of the tire

Inside frame of driver's side door

We always recommend consulting your vehicle owner's manual.

Exploring your sidewallExploring your sidewall

The tire size is a combination of numbers and letters. But what do they actually mean? Lets break it down.

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Tire class
This letter refers to the P-metric(USA) method of tire sizing. In this case, the P stands for Passenger vehicle. "LT" stands for Light Truck. "ST" stands for Special Trailer.
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Tire width
This number refers to the tire's section width, or the distance from sidewall edge to sidewall edge, measured in millimeters up and over the tire's tread. Generally speaking, the larger this number is, the wider the tire will be.
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Aspect ratio
This number is the tire's aspect ratio, or its section height compared to its section width. In this example, the section (or sidewall) height is 70 percent of the section width. This number can be indicative of a tire's purpose. Lower numbers, like 55 or less, mean a short sidewall for improved steering response and better overall handling.
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Internal construction
The "R" refers to radial construction, which has been the industry standard in passenger-car tires for more than 25 years.
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Rim diameter
This is the wheel (or rim) diameter, in inches, for which the tire was sized. Pay particular attention to this number if you plan on upgrading your wheel size. If your wheel diameter changes, you'll have to purchase a new set of tires that matches this new diameter.
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Load index
This number refers to a tire's load index, or how much weight each tire is designed to support. The larger the number, the higher the load capacity. This is one of the most important numbers on your tire.
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Speed rating
The speed rating is a measurement of the speed at which the tire is designed to run for extended periods of time.
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Should I replace 2 tires or 4 tires?
As a general rule, we recommend replacing all four tires at the same time. However, sometimes you may only need to replace two of your tires. If this is the case, we recommend mounting the new tires on the rear axle. This will add traction and increase the overall safety of your vehicle.
Learn more about replacing tires
How can I make my money go farther?
A first glance, it might seem like the best value tire is the one that costs less. But instead of looking at up-front costs, it might be worth looking at the cost over time. When we break down the cost-per-mile, a higher quality tire might end up being the better value. Not to mention improved ride quality, superior handling and enhanced safety. Depending on your driving habits, spending a bit more now could save you money down the road.
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When should I replace my tires?
Knowing when to replace your tires boils down to two simple words: safety first. Keeping track of your tread depth and the age of the tire are two important factors in determining if they’re still safe and road-ready.
Learn more about tire replacement