Load-range ratings for tires are found on the sidewalls. Passenger car tires use name codes, while light trucks use letters. The load range indicates how much load a tire can handle if it is inflated to the proper tire pressure.
Passenger tires fall into three categories, light load (LL), standard load (SL) and extra load XL). Standard load tires are not always marked, but the designation is included in the tire description on the sidewalls. An example is P235/75R-15 SL. Light load tires are usually used for racing or sometimes for small cars that have larger wheels.
European passenger import tires are rated either standard load, reinforced or extra load. The standard load tire may be marked "SL," but the extra load versions are labeled "FX" or "XL." Like the standard tire in American models, the tire category is included in the tire description.
Light truck tires have the load range or the ply rating on the sidewalls and in the tire descriptions. The five load ranges run from "B" to "F," and the five ply ratings from four to 12. A sample tire description would read LT245/75R-16 E. This describes a light truck tire that fits 16-inch wheels and has a load range of "E."