Specifications

Tires and Wheels Preventive Maintenance
– 202 – Y53-6008A
Medium Duty (R05/09)
Tire Inflation
Most tire wear problems are caused by underinflation as the
result of slow leaks. So you will want to check tire pressure
regularly. Give the tires a visual test every day, and check
inflation with a gauge every week.
When checking tire pressure, inspect each tire for damage to
sidewalls, cuts, cracks, uneven wear, rocks between dual
wheels (tires), etc. If a tire appears underinflated, check for
damage to the wheel assembly. Do not forget to check
between dual wheels. If you find wheel damage, have an
expert tire service repair it.
WARNING! Do not repair damaged tires unless
you are fully qualified and equipped to do so.
Wheel and tire assemblies cannot be worked on
without proper tools and equipment, such as:
safety cages or restraining devices. Have all tire
repairs performed by an expert. And stand away
from the tire assembly while the expert is work-
ing.
CAUTION: Pressure should be checked when
the tires are cool. Warm or hot tires cause pres-
sure buildup and will give you an inaccurate
reading. So never deflate a warm tire to the
specified pressure.
Underinflated tires will adversely affect the operation of
the vehicle and tires:
• making steering difficult
• causing extra strain on the tire sidewalls
• reducing the tread life of tires due to the high tempera-
tures generated from excess flexing of the tire
• Inflate tires to the manufacturer's cold air pressure spec-
ification molded into the tire side wall.
Lower tire pressure does not give you more traction on ice or
snow. Underinflation actually reduces traction and steering
control. See the tire manufacturer's Drivers Handbook for
more information on proper operation and use of tires.
Proper Inflation
: the correct
profile for full contact with the
road.
Underinflation
: causes abnor-
mal tire deflection, which builds
up excessive heat, running the
risk of failure. It also causes
irregular wear.
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WITH ROAD
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CONTACT WITH ROAD
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