One thing we sometimes hear from customers buying tires in Puyallup, WA is, “what’s all that information on the tire sidewall mean?” It’s kind of a lot to go into all at once, but let’s see if we can clear it up briefly:
Let’s start with a sidewall stamp of P255/55 R 15 97T. What does that all mean?
P -- denotes a passenger tire. On other tires, LT stands for Light Truck, T for Temporary Spare and ST for Special Trailer.
255 -- This is the section width, measured in millimeters from sidewall to sidewall. In this case, the width of the tire’s tread itself is 255 millimeters.
55 -- This is the aspect ratio; in other words, it’s the height of the sidewall as a portion of the section width. In this case, the sidewall is 55 percent of the 255 millimeters of the width of the tread.
R -- Radial construction
15 -- This tire is designed for a 15” wheel
97 -- This is the tire’s load index designation, indicating the load a tire can safely carry. Load indexes are rated from 0 to 279, while passenger car tires are typically rated between 75 and 105 in the ratings system. In this case, a tire with a rating of 97 can safely carry 1653 pounds; considering that a fully-loaded car might weigh in at 5000 lbs, that’s a pretty generous margin of safety.
T -- This is a speed rating designation. The U.S. government puts minimum speed standards on tires to indicate their ability to maintain a specified speed. Speed ratings range from B (31 mph) to Z (149 mph or over) -- in this case, a T speed rating means this tire is safe up to 118 mph.
There’s a string of other information on tire sidewalls, all encoded for date of manufacture, traction and temperature ratings, tread wear durability and other factors. However, it’s been our experience selling tires in Puyallup, WA that the size designations are the most important thing for most tire buyers to know. If you’ve got any questions or doubts about your tires, schedule an appointment with us at Sea Tac Tire & Auto Tech and we’ll be happy to help!
Technicians here at Sea Tac Tire & Auto Tech believe auto repair and tires are more than a business, they’re our livelihood. Protecting customers of Puyallup, WA with outstanding tires is Sea Tac Tire & Auto Tech’s first priority. Consult our knowledgeable mechanics for all questions or concerns with tires and auto repair in Puyallup, WA!