TIRE SPEED RATINGS
WHAT IS TIRE SPEED RATING？
A tire’s speed rating indicates the optimal speed that the tire can safely maintain over time. In short, it’s the fastest speed a tire can handle before it no longer performs as designed. The higher the speed rating, the better control and handling you’ll have at higher speeds.
The speed rating system was developed to help control the safe performance of tires at standardized speeds. A tire’s certified speed rating is given a letter from A to Z, ranging from 5km/h (3mph) to above 300 km/h (186 mph).
This rating system (see below) shows the top speed for which a tire is certified. It does not indicate the total performance capability of a tire.
WHY WERE TIRE SPEED RATINGS DEVELOPED？
The speed rating system used today was developed in Europe in response to the need to control the safe performance of tires at standardized speeds. When the rating system was originally developed, the "Unlimited V" category of over 210 km/h (130 mph) was the top speed rating possible.
As manufacturers developed bigger and better tires, it became necessary to regulate performance at standardized speeds to ensure safety. The "Limited V" category of 250 km/h (149 mph) was then created, and eventually the "Z" speed rating was added as the top speed rating. (Always consult the manufacturer for the maximum speed of Unlimited Z tires.)
WHERE CAN I FIND MY TIRE SPEED RATING？
You can find your tire speed rating in a number of places, typically in the owner’s manual, driver’s side doorjamb, glove box door, and gas tank hatch. Recent standardization has changed so all ratings except "Unlimited ZR" incorporate the speed symbol and load index as part of every tire’s service description on the tire’s sidewall. If you’re reading your tire sidewall, the speed rating will be the last item in the character sequence in the tire’s size code. Below is an example of a the description on a tire’s sidewall: 2015/60R15 91V. Here, the tire would have a speed rating of V. V-rated tires can be driven at 149 MPH.
205 = Section Width in Millimeters
60 = Aspect Ration
R = Radial Construction
15 = Rim diameter in Inches
91 = Load Index
V = Speed Symbol
TIRE SPEED RATING CHART