
It’s not always easy to understand every inscription and sign when looking at a tire sidewall. While shopping for your new tires, you may need some information in order to make the proper selection.
To learn how to read tire size, click here….
Tire Features
- Tire Type (LT) The first letters listed on the sidewall the type of vehicle on which the tire will fit properly. Here are the possibilities : light trucks (LT), tourisms cars (P), spare tires (T) and tires of special trailers (ST).
- Width (255) Expressed in millimeters, this number corresponds to the thickness (width) of the tire.
- Height / Width Ratio (40%) This percentage is the ratio of the height of the sidewall and the tire width, or the thickness of the sidewall, by the percentage of the width. The higher the ratio (percentage), the higher the tire sidewall, bringing more comfort on the road.
- Construction (R) This letter informs you of the internal construction of the tire. In general, a tire has a radial type of construction (R), that is to say that the textile cords of the carcass completely cover the tire. Other types of construction exist, diagonal (D), for example, or belted (B). The letters “ZR” before the diameter of the wheel do not indicate a construction type, but a speed rating, as explained below. Tires with a speed rating “W” (270 km / h) or Y (300+ km / h) are considered “ZR”.
- Wheel Diameter (17) This measurement in inches indicates the wheel diameter the tire is designed for.
- Overload (XL) The inscription XL after the diameter of the tire means a reinforced tire with a higher load capacity than a standard tire of the same size.
- Load Index This value refers to the maximum weight the tires can carry, considering that they have adequate pressure. You find that real weight in the load table index.
- Speed Rating
This letter refers to the maximum safe speed (in terms of characteristic of the tire, not in the meaning of the law) a tire can support. You can refer to the speed ratings of this charter. It varies between 120km/h and 300km/h).
- Symbol M and S (M+S) A tire with the letters “M” and “S” indicates a confident drive in the mud and snow as it meets the requirements of the Rubber Manufacturers Association.
- European Homologation (E11) This feature certifies that the tire complies with European government standards (reinforced).
- Reinforced Tire “RF” on the sidewall of the tire indicates that it was strengthened to withstand a higher load.
Transport Ministry Security Code
- Security Code (Department of transportation or DOT) The DOT mention on tires ensure compliance with the safety standards of the Department of the US transportation.
- Date of Manufacture (05 11) In this code, the last four digits correspond to the date of fabrication of tires (the week (05) and the year (11)).

- UTQG This section presents the uniform classification of quality of the tire. The UTQG rating (Universal Tire Quality Guide) is based on three criteria that the wear of the tread, traction and temperature.

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