Tires what do the numbers mean

You need to know how to read tire sidewall information, the alphanumeric code stamped on to the side of your tires. But if you've ever looked at the sidewall of a tire and thought that the blizzard of numbers, letters, and words was as confusing as hieroglyphics, we understand. The alphabet soup on tires' sidewalls can be off-putting, but it's pretty easy once you know what you're looking at. Beyond the brand Michelin, Continental, Hankook, etc.

Not to worry. Let us be your Rosetta stone to deciphering the language of the tire sidewall. The numbers highlighted in pink on the sample tire below correspond to the explanations that follow. In this case, the tire is millimeters at its widest point when it's mounted on a wheel of a specified width.

This tire's sidewall height is 40 percent of its width. Sometimes, letters precede the first number. A "P" stands for p-metric, which is a tire used primarily on passenger cars. An "LT" indicates a light-truck tire. A "T" means it's a temporary spare. Find out what your tire numbers mean so you can make the best, most informed decisions about your tire and car care. What do the numbers on this tire mean? In other words, this tire is millimeters wide, from sidewall to sidewall. The majority of tires on the road today are radial tires, in which the internal layers are perpendicular to the axis of rotation and the direction of travel.

These tires have plies that are laid out in a diagonal, or crosshatch, pattern. Our technicians are here for everything you need, from tire repair to tread depth checks. The aspect ratio is indicated on the tire sidewall as a percentage.

In this example, the aspect ratio is 65, meaning the sidewall is 65 percent as high as the tire is wide. To get the sidewall height, take the tire width of mm and convert it to inches 8. This gives you an answer of 5. R is for radial tires, the industry standard for most tires today. They have better road grip, lower rolling resistance for better gas mileage, ride comfort and durability than previous generations of tires. In a radial tire, the plies — layers of strong cords made of a blend of polyester, steel and fabric and coated with rubber — are laid perpendicular to the direction of travel.

D is for tires built with diagonal crisscrossed plies, called bias-constructed tires. They are also called conventional, x-ply, or cross-ply tires. The carrying capacity for each value can be found on a load index chart.

On each U. European tires have the load limit listed in kilograms and sometimes pounds. In this example, the corresponds to 1, pounds see chart below , and the corresponds to 1, pounds.

So which number do you use? The answer is, it depends on the how the tire is being used…and it can change. LT tires are commonly used on trucks with dual rear wheels and are branded with two load indexes.