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Tyre grades
All passenger car tires must conform to Federal Safety requirements, in addition to these grades.
DOT rating
Pirelli P Zero
Tread wear
The tread wear grade is a comparative rating based on the wear rate of the tire when tested under controlled
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 government 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.
Traction
The traction grades, from highest to lowest, are "AA", "A", "B" and "C". Those grades represent the
tyre'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" has poor traction performance.
The traction rating given to a tyre is based on straight line braking tests and does not take other
factors such as acceleration, steering angle, aquaplaning or traction peaks into account.
Temperature
The temperature grades are "A" (the highest), "B", and "C", representing the tyre'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. Grade "C" corresponds to
a minimum level of resistance to which all tyres for cars carrying passengers must comply, according to
what is established by the Federal Standard no. 109 on vehicle safety (Federal Motor Safety Standard).
Grades "B" and "A", measured for tyres on a laboratory test wheel, indicate higher performance levels
than those required by law.
The temperature rating is with reference to a correctly inflated, correctly loaded tyre. Excessive speed,
insufficient inflation, overloading or combinations thereof may cause heat production and possible
tyre failure.
Preparation for tyre removal
Tread wear
220 (Front) – 160
(Rear)
Traction
AA
Temperature
A
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