FORD 2003 Mustang v.1 - Manual (Page 233)

Traction AA A B C
The traction grades, from highest to lowest are AA,
A, B, and C. The grades represent the tire’s ability to
stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have
poor traction performance.
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cornering,
hydroplaning or peak traction characteristics.
Temperature A B C
The temperature grades are A (the highest), B and
C, representing the tire’s resistance to the
generation of heat and its ability to dissipate heat
when tested under controlled conditions on a
specified indoor laboratory test wheel. Sustained
high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure. The
grade C corresponds to a level of performance which
all passenger car tires must meet under the Federal
Motor Vehicle Safety Standard No. 109. Grades A
and B represent higher levels of performance on the
laboratory test wheel than the minimum required by
law.
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause heat
buildup and possible tire failure.
Maintenance and Specifications
233