See also:

Traction AA, A, B and 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 under controlled conditions on specified government test ...

Wheels and tires
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Wheel balance
Unbalanced wheels may affect vehicle handling and tire life. Even with regular use, wheels can get out of balance. Therefore, they should be balanced as required. Wheel balance service should be perf ...