Storing Tires; Cleaning - SMART fortwo coupe Operator's Manual

Tires and wheels
128
Depending upon the weather and/or road
surface (conditions), the tire traction
varies widely.
Do not allow your tires to wear down too far.
Adhesion properties on wet roads are
sharply reduced at tread depths of less than
1
/ in (3 mm).
8
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of
approximately
point the tire is considered worn and
should be replaced.
Recommended minimum tire tread depth:
1
Summer tires /
1
Winter tires /
6
Treadwear indicator : appears as a solid
band across the tread.

Storing tires

!
Keep unmounted tires in a cool, dry
place with as little exposure to light as
possible. Protect tires from contact with
oil, grease and fuels.
Cleaning tires
!
Never use a round nozzle to power wash
tires. The intense jet of water can result
in damage to the tire.
Always replace a damaged tire.
1
/ in (1.6 mm), at which
16
in (3 mm)
8
in (4 mm)
Uniform Tire Quality Grading
Standards
The Uniform Tire Quality Grading is a U.S.
Government requirement designed to give
drivers consistent and reliable
information regarding tire performance.
Tire manufacturers are required to grade
tires based on three performance factors:
treadwear :, traction ;, and temperature
resistance =. Although not a Government
of Canada requirement, all tires made for
sale in North America have these grades
branded on the sidewall.
i
For illustration purposes only. Actual
data on tires are specific to each vehicle
and may vary from data shown in above
illustration.
Quality grades can be found, where
applicable, on the tire sidewall between
tread shoulder and maximum section width.
For example:
Treadwear Traction
200 AA
All passenger car tires must conform to
federal safety requirements in addition to
these grades.
Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the tire
when tested under controlled conditions on
a specified U.S. government test course.
Temperature
A