Chrysler 2005 PT Cruiser - Manual (Page 348)

WARNING!
The traction grade is based on braking (straight-
ahead) traction tests and does not include cornering
(turning) performance.
Temperature Grades
The temperature grades are A (highest), B, and C, repre-
senting 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 passen-
ger car 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.
WARNING!
The temperature grade 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.
348 IF YOU NEED CONSUMER ASSISTANCE