Chevrolet 1993 Corvette Owner's Manual page 287

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Service & Appearance Care
Tra~ti~n-A, 6, C
3 3 % traction grades, from highest to
.lowest are: A, B, and
C.
They 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 podr.traction p-erformance.
Warning: The traction grade assigned
to. this tire is based on braking (straight-
ahead) traction tests and does not
include cornering (turning) traction.
186.
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 inaterid af the tire to
degenwate.-and reduce tire @e, and
excessive temperature can lead to.
sudden tire failure. The-grade
C
corresponds
t o .
a level of performance
which d l passenger car tires must meet
under:the Federal Motor Vehicle Sa€ety
Standard NO..
109.
Grades B.and A
represent higher levels of perfomnance on
the laboratory test wheel than the
minimum required by law.
Warning: The temperatute grade for
this tire 'is established for a tire that is
properly inftated and not overloaded.
Excessive speed, underinflation, or
excessive loading, iither separately or in
combination, cah cause heat buildup
and possible tire failure.
Those grades are molded on the
sidewalls of passenger car tires.
While the tires available
as
standard or
optional equipment on General Motors
vehicles may vary with. respect to these
grades, all such tires meet Gene$d.
Motors performance standards and
have been appToved for use
QII
General
Motors vehicles. All passenger type
(P Metric) tifes .must conform to federal
safety requirements in addition to these.
grades.