Jeep 2013 Grand Cherokee, Operating Information Manual

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Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a comfortable
ride. Over-inflation produces a jarring and un-
comfortable ride. Both under-inflation and over-
inflation affect the stability of the vehicle and
can produce a feeling of sluggish response or
over responsiveness in the steering.
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.
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 in-
flated even when they are under-inflated.
•
Inspect tires for signs of tire wear or visible
damage.
CAUTION!
After inspecting or adjusting the tire pres-
sure, always reinstall the valve stem cap.
This will prevent moisture and dirt from en-
tering the valve stem, which could damage
the valve stem.
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 a three hour period. The cold tire inflation
pressure must not exceed the maximum infla-
tion 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 in-
creased 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 pres-
sure will be too low.
Tire Pressures For High Speed
Operation
The manufacturer advocates driving at safe
speeds and within posted speed limits. Where
speed limits or conditions are such that the
vehicle can be driven at high speeds, maintain-
ing correct tire inflation pressure is very impor-
tant. Increased tire pressure and reduced ve-
hicle loading may be required for high-speed
vehicle operation. Refer to your authorized tire
or original equipment vehicle dealer for recom-
mended safe operating speeds, loading and
cold tire inflation pressures.
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