en.m.wikipedia.org/wiki/Uniform_Tire_Quality_Grading 可以看 traction 那一个项目 “The testing does not take into account cornering, hydroplaning, acceleration or stopping on a dry surface. Nor does it account for the significantly different effectiveness of ABS versus non-ABS braking systems on a tire's stopping distance. The UTQGS traction test procedure measures a tire's coefficient of friction when it is tested on wet asphalt and concrete surfaces. The test tire is installed on an instrumented axle of a traction trailer, which is towed by a truck at 40 miles per hour (mph) over wet asphalt and concrete surfaces. The tow truck is equipped with an on-board water supply system that sprays water in front of the test tire. ”