What is P215 on a tire?
Tire Size. The first set of numbers on a tire sidewall is the tire size. For example, if you see P215/65R15, this means: P = Passenger tire. Width of the tire in millimeters. R17 tires have a diameter of 26. The sidewall of the tire is 4.A 215/55R17 tire has an overall diameter of 26. Its circumference is approximately 82.