For 1990-2009 cars only
Most tires have a service description branded on the sidewall after the tire size. The service description consists of two parts:
| • | The load index is a number usually between 75 and 115. The load index number defines the tire's load capacity at maximum inflation. The higher the number the greater the load capacity. |
| • | The speed symbol is the letter between P and Z. The speed symbol letter defines the speed capacity of the tire. The speed symbol letter is part of the tire size with some V and Z rated tires. |
Tire companies have charts which define equivalent loads and speed for all load indexes and speed symbols that make up the tire service description.
Important: Never install replacement tires that are a smaller size or a lesser speed rating than the original equipment. The speed ratings apply when the tire is fully inflated. An under-inflated tire will not meet its speed rating capability. For tire speed ratings, refer to Tire and Wheel Specifications .
