2020 RAM 1500 Owner’s Manual — DEPARTMENT OF TRANSPORTATION UNIFORM TIRE QUALITY GRADES

Tire Rotation (Rearward Cross)

All passenger vehicle tires must conform to Federal safety requirements in addition to these grades.

Treadwear

The Treadwear grade is a comparative rating, based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and one-half times as well on the government course as a tire graded

100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices, and differences in road charac- teristics and climate.

Traction Grades

The Traction grades, from highest to lowest, are AA, A, B, and C. These grades represent the tire's ability to stop on wet pavement, as measured under controlled conditions on spec- ified government test surfaces of asphalt and concrete. A tire marked C may have poor traction performance.

The Temperature grades are A (the highest), B, and C, repre- senting the tire's resistance to the generation of heat and its ability to dissipate heat, when tested under controlled condi- tions on a specified indoor laboratory test wheel.