If you’ve ever done research on tires, there’s no doubt you’ve heard people discuss tire ratings and grades. If you’re not entirely sure what these ratings and grades mean, it can be difficult to figure out which ones are the best. Tire ratings denote your tire’s composition and expected performance while driving. Once you understand how to read tire ratings, you’ll be able to better choose the tires to fit your driving style.
Decoding Your Tire’s Sidewall
Typically, tire sidewalls contain a wealth of information. In addition to your tire size and manufacturer information, it’s also where you’ll find your tire ratings and grades. With a clearer picture of what you’re looking at on your tire’s sidewall, the information it contains will quickly begin to make more sense.
A Breakdown of Different Tire Ratings and Grades
Let’s take a closer look at some of the information you will find on your tire’s sidewall.
Treadwear Grade – This is a numerical rating of a tire’s wear rate when tested under controlled conditions. For example, if you have a tire that has a treadwear grade of 300, that tire would wear three times as well as a tire graded 100 under the same conditions. It’s important to note that driver habits and road conditions can also play a factor in tire wear, and this number is only representative of a specific controlled environment.
Traction Grade – This grade is a reflection of a tire’s ability to maneuver and brake while driving on wet pavement. There are four different traction grades:
AA is the best traction grade, while C is the worst. If a tire has a traction grade of AA, you can be confident in its ability to navigate and handle on wet surfaces. Conversely, a tire with a traction grade of C may have difficulty in wet and rainy weather. If you live in an area where it rains frequently, you’ll want to invest in tires with a high traction grade.
Temperature Grade – This grade reflects a tire’s ability to effectively dissipate heat. From highest (able to dissipate the most heat) to lowest (less able to dissipate heat), temperature grades are:
A high temperature grade is important because it indicates your tire will maintain its structural integrity when faced with extreme temperatures. High temperatures can cause tires with lower temperature grades to experience cracked treads, bubbling sidewalls, and even blowouts. The higher the temperature grade, the more likely it is that your tires will be continue to provide effective handling and performance when the weather gets warm. This is particularly important for drivers who spend a lot of time commuting at high speeds in the summer.
Load Index – This index refers to the weight that a tire can safely carry. A typical load index for a tire on a mid-sized vehicle is 95. This rating means that each tire can carry a maximum of 1521 pounds.
Speed Rating – Your tire’s speed rating is indicated by a letter, and represents its maximum speed when carrying its maximum load (which is defined by the load index). A typical speed rating for a family sedan is S (a maximum speed of 180 km/h), while a sport sedan tire may have a speed rating of H (a maximum speed of 210 km/h). The following is a list of Canadian speed ratings as well as their corresponding maximum speeds:
- L – 120 km/h
- M – 130 km/h
- N – 140 km/h
- Q – 160 km/h
- R – 170 km/h
- S – 180 km/h
- T – 190 km/h
- U – 200 km/h
- H – 210 km/h
- V – 240 km/h
- Z – 240+ km/h
- W – 270 km/h
- Y – 300 km/h
- (Y) – 300+ km/h
Understanding Your Tire’s Capabilities is the Best way to Make an Informed Purchase
When you know what a tire’s ratings and grades mean, you’re better able to find the ones that are perfect for your driving style, as well as your vehicle. To learn more about tire ratings and how they impact your vehicle, stop into your local Tirecraft and speak with our experts today. They’ll be more than happy to answer any questions you may have and assist you in choosing the right tires for your needs.