Lincoln 2013 MKZ, Owner'S Manual

Page: 308 / 474

Treadwear
The treadwear 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
½) 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 AA A B C
WARNING
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.
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.
Temperature A B C
WARNING
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.
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.
139. Grades B and A represent higher
levels of performance on the
laboratory test wheel than the
minimum required by law.
305
Wheels and Tires