741
Maintenance
Temperature -A, B & C
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 condi-
tions 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 cor-
responds to a level of performance
which all passenger car tires must
meet under the Federal Motor
Vehicle Safety Standard No. 109.
Grades B and A represent higher
levels of performance on the labora-
tory test wheel than minimum
required by law.Tire terminology and definitions
Air Pressure
: The amount of air
inside the tire pressing outward on
the tire. Air pressure is expressed in
pounds per square inch (psi) or kilo-
pascal (kPa).
Accessory Weight : This means the
combined weight of optional acces-
sories. Some examples of optional
accessories are, automatic transmis-
sion, power seats, and air condition-
ing.
Aspect Ratio : The relationship of a
tire's height to its width.
Belt: A rubber coated layer of cords
that is located between the plies and
the tread. Cords may be made from
steel or other reinforcing materials.
Bead : The tire bead contains steel
wires wrapped by steel cords that
hold the tire onto the rim.
Bias Ply Tire : A pneumatic tire in
which the plies are laid at alternate
angles less than 90 degrees to the
centerline of the tread.WARNING - Tire temperature
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
build-up and possible sudden
tire failure. This can cause loss
of vehicle control and serious
injury or death.
WARNING
The traction grade assigned to
this tire is based on straight-
ahead braking traction tests,
and does not include accelera-
tion, cornering, hydroplaning,
or peak traction characteristics.
WARNING
The temperature grade for this
tire is established for a tire that
is properly inflated and not
overloaded. Excessive loading,
either separately or in combina-
tion, can cause heat build-up
and possible tire failure.
Maintenance
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7
Aluminum wheel maintenance
The aluminum wheels are coated with a
clear protective finish.
Do not use any abrasive cleaner, pol-
ishing compound, solvent, or wire
brushes on aluminum wheels. They
may scratch or damage the finish.
Use only a mild soap or neutral deter- gent, and rinse thoroughly with water.
Also, be sure to clean the wheels after
driving on salted roads. This helps pre-
vent corrosion.
Avoid washing the wheels with high- speed car wash brushes.
Do not use any cleaners containing acid or acid detergents. It may damage
and corrode the aluminum wheels
coated with a clear protective finish.
Corrosion protection
Protecting your vehicle from corro-sion
By using the most advanced design and
construction practices to combat corro-
sion, we produces cars of the highest
quality. However, this is only part of the
job. To achieve the long-term corrosion
resistance your vehicle can deliver, the
owner's cooperation and assistance is
also required.
Common causes of corrosion
The most common causes of corrosion
on your car are:
allowed to accumulate underneath the
car.
Removal of paint or protective coatings by stones, gravel, abrasion or minor
scrapes and dents which leave unpro-
tected metal exposed to corrosion.
High-corrosion areas
If you live in an area where your car is
regularly exposed to corrosive materials,
corrosion protection is particularly impor-
tant. Some of the common causes of
accelerated corrosion are road salts,
dust control chemicals, ocean air and
industrial pollution.
Moisture breeds corrosion
Moisture creates the conditions in which
corrosion is most likely to occur. For
example, corrosion is accelerated by
high humidity, particularly when tempera-
tures are just above freezing. In such
conditions, the corrosive material is kept
in contact with the car surfaces by mois-
ture that is slow to evaporate.
Mud is particularly corrosive because it is
slow to dry and holds moisture in contact
with the vehicle. Although the mud
appears to be dry, it can still retain the
moisture and promote corrosion.
High temperatures can also accelerate
corrosion of parts that are not properly
ventilated so the moisture can be dis-
persed. For all these reasons, it is par-
ticularly important to keep your car clean
and free of mud or accumulations of
other materials. This applies not only to
the visible surfaces but particularly to the
underside of the car.
