traction control TOYOTA PRIUS 2005 2.G Owners Manual

223
—Uniform tire quality grading
This information has been prepared
in accordance with regulations issued
by the National Highway Traffic Safe-
ty Administration of the U.S. Depart-
ment of Transportation. It provides
the purchasers and/or prospective
purchasers of Toyota vehicles with in-
formation on uniform tire quality grad-
ing.
Your Toyota dealer will help answer
any questions you may have as you
read this information.
DOT quality grades—All passenger
car tires must conform to Federal
Safety Requirements in addition to
these grades. Quality grades can
be found where applicable on the
tire sidewall between tread shoul-
der and maximum section width.
For example: Treadwear 200 Trac-
tion AA Temperature A.Tread wear—
The tread wear grade
is a comparative rating based on the
wear rate of the tire when tested un-
der controlled conditions on a speci-
fied government test course. For ex-
ample, a tire graded 150 would wear
one and a 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 hab-
its, service practices and differences
in road characteristics and climate. Traction AA, A, B, C—
The traction
grades, from highest to lowest, are
AA, A, B, and C, and they represent
the tire’s ability to stop on wet pave-
ment as measured under controlled
conditions on specified government
test surfaces of asphalt and concrete.
A tire marked C may have poor trac-
tion performance.
Warning: The traction grade assigned
to this tire is based on braking
(straight ahead) traction tests and
does not include cornering (turning)
traction.

2322. Summer tires
Summer tires are high −speed capabil-
ity tires best suited to highway driving
under dry conditions.
Since summer tires do not have the
same traction performance as snow
tires, summer tires are inadequate for
driving on snow −covered or icy roads.
For driving on snow −covered or icy
roads, we recommend using snow
tires. If installing snow tires, be sure
to replace all four tires.
The details about how to distinguish
summer tires from all season tires are
described on page 218.
CAUTION
 Do not mix summer and all sea-
son tires on your vehicle as
this can cause dangerous han-
dling characteristics, resulting
in loss of control.
 Do not use tire other than the
manufacturer’s designated
tires, and never mix tires or
wheels of the sizes different
from the originally equipped
tires and wheels.

296 When rotating tires, check for uneven
wear and damage. Abnormal wear is
usually caused by incorrect tire infla-
tion pressure, improper wheel align-
ment, out−of −balance wheels, or se-
vere braking.
CAUTION
Do not include a compact spare
tire when rotating the tires. It is
designed for temporary use only.
WHEN TO USE SNOW TIRES OR
CHAINS
Snow tires or chains are recommended
when driving on snow or ice.
On wet or dry roads, conventional tires
provide better traction than snow tires.
SNOW TIRE SELECTION
If you need snow tires, select tires of
the same size, construction and load
capacity as the originally installed tires.
Do not use tires other than those men-
tioned above. Do not install studded tires
without first checking local regulations for
possible restrictions.
CAUTION
Do not use snow tires other than the
manufacturer ’s recommended size, as
this may cause dangerous handling
characteristics resulting in loss of
control. Otherwise, an accident may
occur resulting in death or serious
injuries.
SNOW TIRE INSTALLATION
Snow tires should be installed on all
wheels.
Installing snow tires on the front wheels
only can lead to an excessive difference
in road grip capability between the front
and rear tires which could cause loss of
vehicle control.
When storing removed tires, you should
store them in a cool dry place.
Mark the direction of rotation and be sure
to install them in the same direction when
replacing.
CAUTION
Do not drive with the snow tires
incorrectly inflated.
Never drive over 120 km/h (75 mph)
with any type of snow tires.
Installing snow tires and
chains