Y speed rating
Y at the end of a tire’s service description, as in 93Y, is the speed rating for 300 km/h (186 mph). In brackets, (Y) means over 300 km/h.
How to read it
On the chart used by USTMA and Bridgestone, Y is 300 km/h (186 mph), the highest letter, above W at 270 km/h (168 mph). Michelin gives Y as 186 mph; Ford’s manual converts it as 299 km/h. See the full chart.
Also searched as: Y rated tire.
What each marking means under the standard that defines it. This page describes markings; it doesn’t advise on choosing, fitting, inflating or replacing tires.
Y and (Y)
USTMA says a tire rated above 300 km/h (186 mph) must have a Z in its size and a service description with the Y in brackets. Its examples: P275/40ZR17 93Y is rated for 186 mph; P275/40ZR17 (93Y) is over 186 mph, and USTMA refers to the tire’s maker for the figure. See ZR in a tire size.
More tire sidewall markings
Browse symbols drawn with curves and waves or letters and numbers.
Sources
- Tire Care and Safety Guide, U.S. Tire Manufacturers Association (USTMA), Speed Symbol, p. 8
- Replacement Tire Selection Manual, Ref. No. P-06-01, August 2006, Bridgestone Americas, p. 7
- Tire Load Rating & Speed Rating Explained, Michelin North America, FAQ
- Speed and Load Rating Charts Explained, Bridgestone Australia, Tyre speed symbol table
- 2024 Ford Escape Owner’s Manual, Ford Motor Company, Wheel and Tire Information, p. 386
Last reviewed September 29, 2026 by Rory Hansen. How we research