Decoding tire lingo
All tires are different but they are rated on a common scale, so you can do some comparison shopping. Aside from size, one of the most essential codings is the speed rating, contained in the basic description code of the tire. For example, in P275/45R18 95V, the last letter is the speed rating, "V," which means the tire is good for up to 149 mph. You'll also notice a treadwear rating--a long-life, all-season tire would have a treadwear rating of 450 and 170 would be at the low end would only last about a year. To see a chart with all of the decoding explained, click here.