View Here : How To Read A Tire Size
245: The width of the tire, from sidewall to sidewall, in millimeters. A 245 is 245 millimeters, or 24.5 centimeters, wide. The tread width is actually somewhat smaller than the tire's actual width. 45: Aspect Ratio. This is the sidewall's height from the inside diameter to the outside diameter.
That index can then be converted to pounds by looking at the Tire Load Index Chart. Our example tire has an index of 98. After a quick glance at the chart, this equates to 1,653 pounds. Speed Rating . The final letter found on your tire size marking is the maximum speed for a tire. Each letter correlates to a given speed in MPH.