Uniform tire quality grading (us), Treadwear, Traction – Saab 2000 9-5 User Manual

Page 200: Wear indicators

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200

Car care and technical information

Uniform Tire Quality Grading (US)

Quality grades can be found where applica-
ble on the tire sidewall between tread shoul-
der and maximum section width. For exam-
ple:
Treadwear 200 Traction AA
Temperature A

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 1/2) times as well on the gov-
ernment 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 character-
istics and climate.

Traction

The traction grades, from highest to lowest,
are AA, A, B and C. These 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.

Wear indicators

The tires incorporate wear indicators in the
form of smooth, treadless strips across the
width, which become visible when only
1.6 mm of tread remains. As soon as the
indicators become visible, new tires should
be fitted without delay.
Make sure you are familiar with the legal
limit for minimum tread depth in your
country and also any regulations gov-
erning the use of winter tires.

WARNING

The traction grade assigned to a tire is
based on straight-ahead braking, traction
test and does not include acceleration,
cornering, hydroplaning or peak traction
characteristics.

SG840

Wear indicators

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