People often ask us questions about snow tires or winter tires. Those terms are used interchangeably. Tires designed for use in severe snow conditions generally have tread patterns, structure, and materials to give superior performance in snow over tires meeting the RMA Snow Tire Definition.
Tires designed for use in severe snow conditions are recognized by manufacturers to attain a traction index equal to or greater than 110 compared to the ASTM E-1136 Standard Reference Test Tire when using ASTM F-1805, 2006 snow traction test with medium packed snow surface and equivalent percentage loads. Other test methods and reference tires developed by standardizing bodies may be used provided proper correlations are demonstrated.
Tires designed for use in severe snow conditions are marked on at least one sidewall with the letters “M” and “S” (e.g., MS, M/S, M&S, M+S, etc.) plus a pictograph of a mountain with a snowflake. The mountain profile shall have a minimum base of 15 mm and a minimum height of 15 mm and shall contain three-peaks with the middle peak being the tallest. Inside the mountain there shall be a six-sided snowflake having a minimum height of one-half the tallest peak. An example of the mountain/snowflake is shown above.Top