Commercial vehicles often require tires able to withstand heavy loads, wide turns and long trips on the open road. Trucks used to haul freight deliveries, transfer employees to and from jobs and carry equipment can benefit from tires with durable tread design and width specifications. Many commercial tires can be custom designed to suit the needs of company vehicles to ensure maximum reliability and cost savings.
Commercial tire users often require access to important information that relates to design and function. Information specs are almost always branded along the exterior side of the tire. Codes are scripted in alphabetical and numerical codes which display pertinent information to the tire model. Codes may communicate data relevant to length, width and height dimensions, weight bearing limits, maximum range temperature and reliability at maximum velocity.
Many commercial tire information codes begin or end with one or two letters. According to Tire Tech, these letters indicated the type of vehicle the tire is designed to fit. Any code starting with letters "LT" indicate that the tire is designed to fit a "Light Truck-metric" vehicle -- a sport utility or company truck, for example -- capable of carrying heavy cargo or towing large trailers. "C" codes indicate a tire is manufactured for commercial use on vans or trucks built to withstand lots of weight. Additionally, "ST" codes are almost exclusively used for Special Trailer Service -- or commercial trailers -- only and are not for standard passenger vehicles. Any other single or double digit letters often stand for internal construction data.
Once the beginning letter is identified, most codes continue with a series of digits. The three numbers following the first letter indicate the millimeter width of the tire. For example, a "230" code stands for 230 millimeters. The next two digits measure the height of the tire in millimeters. The two digits after the height measurement equal the rim diameter in inches. The last dual set of numbers indicates the "service description" which stands for the "tire's Load Index and Speed Rating."
