SERVICING AND MAINTENANCE
222
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the
safe and satisfactory operation of your vehicle.
Four primary areas are affected by improper tire
pressure:
Safety
Fuel Economy
Tread Wear
Ride Comfort and Vehicle Stability
Safety Both underinflation and overinflation affect the
stability of the vehicle and can produce a feeling
of sluggish response or over responsiveness in
the steering.
NOTE:
Unequal tire pressures from side to side may
cause erratic and unpredictable steering
response.
Unequal tire pressure from side to side may
cause the vehicle to drift left or right.
Fuel Economy
Underinflated tires will increase tire rolling
resistance resulting in higher fuel consumption.
Tread Wear
Improper cold tire inflation pressures can cause
abnormal wear patterns and reduced tread life,
resulting in the need for earlier tire replacement.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a comfortable
ride. Overinflation produces a jarring and
uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed on
the driver's side B-pillar or rear edge of the
driver's side door.
At least once a month:
Check and adjust tire pressure with a good
quality pocket-type pressure gauge. Do not
make a visual judgement when determining
proper inflation. Tires may look properly
inflated even when they are underinflated.
Inspect tires for signs of tire wear or visible
damage. Inflation pressures specified on the placard are
always “cold tire inflation pressure”. Cold tire
inflation pressure is defined as the tire pressure
after the vehicle has not been driven for at least
three hours, or driven less than 1 mile (1.6 km)
after sitting for a minimum of three hours. The
cold tire inflation pressure must not exceed the
maximum inflation pressure molded into the tire
sidewall.
Check tire pressures more often if subject to a
wide range of outdoor temperatures, as tire
pressures vary with temperature changes.
Tire pressures change by approximately 1 psi
(7 kPa) per 12°F (7°C) of air temperature
change. Keep this in mind when checking tire
pressure inside a garage, especially in the Winter.
Example: If garage temperature = 68°F (20°C)
and the outside temperature = 32°F (0°C) then
the cold tire inflation pressure should be
increased by 3 psi (21 kPa), which equals 1 psi
(7 kPa) for every 12°F (7°C) for this outside
temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to
40 kPa) during operation. DO NOT reduce this
normal pressure build up or your tire pressure will
be too low.
WARNING!
Improperly inflated tires are dangerous and
can cause collisions.
Underinflation increases tire flexing and can
result in overheating and tire failure.
Overinflation reduces a tire's ability to
cushion shock. Objects on the road and
chuckholes can cause damage that result in
tire failure.
Overinflated or underinflated tires can affect
vehicle handling and can fail suddenly,
resulting in loss of vehicle control.
Unequal tire pressures can cause steering
problems. You could lose control of your
vehicle.
Unequal tire pressures from one side of the
vehicle to the other can cause the vehicle to
drift to the right or left.
Always drive with each tire inflated to the
recommended cold tire inflation pressure.
CAUTION!
After inspecting or adjusting the tire pressure,
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the
valve stem, which could damage the valve
stem.
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