Tire Standards

There is also one special ultrahigh speed rating: If a Y-rated tire has parentheses around its service description, say, “(93Y),” that means the tire is rated for speed “in excess of 186 mph.” There are also Z-rated tires, but when that designation came out, no one thought a speed rating in excess of 149 mph…

Tire load and inflation table for P-Metric tire sizes with corresponding tire inflation pressures and load carrying capacities. P-Metric tire sizes come with Light Load (LL), Standard Load (SL) and Extra Load (XL) designations. P-Metric sizes with Light Load (LL) and Standard Load (SL) designations have the maximum load capacity at 35 or 36 psi,…

There are two major size designations commonly used for passenger car tires, called P-metric and Metric sizing. If you see a “P” in front of the tire size displayed on a tire’s sidewall it is a P-metric tire. If there’s no P, it’s a Metric tire (also called Euro-metric or Hard-Metric). In the past, P-metrics…