Understanding Tire Speed Ratings
Discover Your Tire Speed Rating
If you didn’t even know that tires have a top speed, you’re not alone. However, every tire sold has a specific “tire speed rating” that tells you the range of speeds your tire is certified to safely handle under specific service conditions. However, finding a tire’s speed rating takes a bit of insider knowledge.
Every tire has a service description, which probably looks like a jumble of letters and numbers to most people. The tire speed rating is listed at the very end of the service description and it’s indicated by a letter, A through Y. The following chart breaks down one of these service descriptions. In 205/60R15 91V, the speed rating is represented by the letter V.
|205 = Section Width in Millimeters|
|60 = Aspect Ratio|
|R = Radial Construction|
|15 = Rim Diameter in Inches|
|91 = Load Index||(Service
|V = Speed Symbol|
You don’t need to crawl around on the ground, examining your tires to discover your tire speed rating. You can find the tire speed rating recommended by the manufacturer in your manual, and also in various places inside the car that list the recommended tire service code (i.e. the driver’s side door, inside the glove box, and so on).
The Tire Speed Rating Chart
Noting the tire speed rating is one thing, but actually understanding what it means is another! That is where our tire speed rating chart below comes into play. Let’s continue with the example tire above, 205/60R15 91V. Once you’ve determined that “V” is the speed rating, you can use the chart to determine what speeds that tire can handle.
|Speed Symbol||Speed (km/h)||Speed (mph)|
A tire with a “V” speed rating can handle 240 km/hr, or 149 mph. When tires have a maximum speed capability above 149 mph (240 km/h), a “ZR” may appear in the service description. If it can handle over 186 mph (300 km/h), it must have a “ZR” in the description.:
|Tire Designation||Maximum Speed|
|P275/40ZR17 93W||270 km/h (168 mph)|
|P275/40ZR17 93Y||300 km/h (186 mph)|
An Important Reminder
The tire speed rating on your vehicle’s tires will likely exceed posted speed limits. This doesn’t mean you should put the pedal to the metal! Rather, these speed ratings simply inform you that in laboratory testings, tires could perform as designed up to that speed. Road, weather, and vehicle conditions can affect your tires, so this rating does not mean it is necessarily safe to drive at that speed.
If you have questions about your tires, feel free to stop by your local Wheel Works and talk with a technician. We’re open seven days a week for your convenience!