Customer Information and Reporting Safety Defects; Uniform Tire Quality Grading System (UTQGS)- Page 475

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Customer Information and Reporting Safety Defects

Uniform Tire Quality Grading System (UTQGS)

             Uniform  Tire  Quality  Grading  System  (UTQGS)

    This information relates to the tire grading system developed by the U.S. National Highway 
Traffi c Safety Administration for grading tires by tread wear, traction, and temperature 
performance.

 Tread  Wear

    The tread wear grade is a comparative rating based on the wear rate of the tire when tested 
under controlled conditions on a specifi ed government test course.
  For example, a tire graded 150 would wear one-and-a-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 signifi cantly from the norm because of variations in driving habits, service 
practices and differences in road characteristics and climate.

 Traction-AA, A, B, C

    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 specifi ed 
government test surfaces of asphalt and concrete. A tire marked C may have poor traction 
performance.

WARNING

  The traction grade assigned to this tire is based on braking (straight ahead) traction tests 
and does not include acceleration cornering (turning), hydroplaning, or peak traction 
characteristics.

 Temperature-A, B, C

    The temperature grades A (the highest), B, and C, represent the tire's resistance to the 
generation of heat and its ability to dissipate heat when tested under controlled conditions on 
a specifi ed indoor laboratory test wheel.
  Sustained high temperature can cause the material of the tire to degenerate and reduce tire 
life, and excessive temperatures can lead to sudden tire failure.

  Grade C corresponds to a level of performance which all passenger vehicle tires must meet 
under the Federal Motor Vehicle Safety Standard No. 109. Grades B and A represent higher 
levels of performance on the laboratory test wheel than the minimum required by law.