FORD 1998 Taurus - Manual (Page 151)

U.S. Department of Transportation-Tire quality
grades: The U.S. Department of Transportation
requires Ford to give you the following information
about tire grades exactly as the government has
written it.
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 grade 150 would wear
one and one-half (1 1/2) times as well on the
government course as a tire grade 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 A B C
The traction grades, from highest to lowest are A, B,
and C, and they represent the tire’s ability to stop
on wet pavement as measured under 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 braking (straight ahead) traction
tests and does not include cornering (turning)
traction.
Maintenance and care
151