How to Compare 16-Inch Tires to 17-Inch Tires
- 1). Look at the tire code. It will begin with numbers. Following the numbers will be a group of numbers. These numbers represent the size, when mounted, of the tire from the widest point of the outside of the sidewall to the widest point of the inside sidewall of the of the tire, in millimeters.
- 2). Check the numbers following the letters and first set of numbers. You will now see an additional three digits that are used to identify the tire's section width in millimeters. Following this set of numbers, you will see a letter. The letter is used to identify the tire's internal construction.
- 3). Look at the numbers that follow the previous letters and numbers. For a 16-inch tire you will see 16 and for a 17-inch tire, you will see 17. Example: P225/50R16 91S . The last set of numbers and letter is for the service description.
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