All those numbers molded onto the side of your tire actually mean something! Here are some tips on how to read a tire:
-The width of the tire tread in millimeters. This is important to know, since if your replacement tire doesn’t match factory specification, your replacement tire may not fit on your wheel/rim, or if it fits, you may have interference between the tires and the chassis or body. Be sure and take notes or pictures of your current tire width if you’re looking to replace it with the same specifications.
-The height of the tire sidewall as a percentage of the tire width. The higher this number, the taller the tire is (assuming the tire width remains constant). For example, a 225/35/R17 tire has aspect ratio of 35. If compared with a 225/65/R17 tire, the 65 aspect ratio tire will be taller. Higher aspect ratio tires generally are designed to provide more air cushioning or ‘compliance’ to provide a more supple and comfortable ride. But as the aspect ratio increases (and ride comfort increases), it reduces it’s sporty or responsive character compared to a lower aspect ratio tire.
-R stands for “radial” tire construction. The number is the diameter of the wheel rim, in inches. Be sure the replacement tire diameter matches the wheel you are planning to have it installed on. It makes for a bad day when you try to mount a 17″ tire onto a 18″ wheel 🙁
It’s important to have the correct tire sizes that will fit your wheels correctly (some vehicles have different front and rear tire/wheel sizes). Buying tires that are not the correct factory specification may lead to interference with chassis/suspension/body components.
If you’re interested in changing the size of your wheel/tire package (Plus Sizing or Down Sizing) – check out this link for Plus Sizing Explained.
Still looking for more info on other tire markings you’re curious about? Jump over to our “How to Read a Tire, Part 2” to find out what those other numbers and symbols mean
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