Subaru Impreza Manuals 2017 Impreza Owner's Manual | Page 457

Consumer information and Reporting safety defects/Uniform tire quality grading standards reduced by 32 lbs (15 kg) or more. 13-15 Uniform tire quality grading standards All passenger car tires must con- form to Federal Safety Require- ments in addition to these grades. This information indicates the rela- tive performance of passenger car tires in the area of treadwear, traction, and temperature resis- tance. This is to aid the consumer in making an informed choice in the purchase of tires. Quality grades can be found where applicable on the tire sidewall be- tween tread shoulder and maxi- mum section width. For example: & Treadwear The treadwear grade is a compara- tive rating based on the wear rate of the tire when tested under con- trolled conditions on a specified government test course. For example, a tire graded 150 would wear one and one-half (1- 1/2) times as well on the govern- ment 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 characteristics and climate. Treadwear 200 Traction AA Tem- perature A The quality grades apply to new pneumatic tires for use on passen- ger cars. However, they do not apply to deep tread, winter type snow tires, space-saver or tempor- ary use spare tires, tires with nominal rim diameters of 12 inches or less, or to some limited produc- tion tires. & Traction AA, A, B, C The traction grades, from highest to lowest, are AA, A, B and C. Those grades represent the tire’s ability to stop on wet pavement as measured – CONTINUED –