2007 JEEP GRAND CHEROKEE Owners Manual

check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
CAUTION!
After inspecting or adjusting the tire pressure al-
ways reinstall the valve stem cap–if equipped. This
will prevent moisture and dirt from entering 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 3 hours, or driven less than 1 mile
(1 km) after a 3 hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire side wall.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.
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Tire Pressures for High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maximum
load is dangerous. The added strain on your tires could
cause them to fail. You could have a serious accident.
Don’t drive a vehicle loaded to the maximum capacity
at continuous speeds above 75 mph (120 km/h).
Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial tires in sets of four. Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
dealer for radial tire repairs.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).
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WARNING!
Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure
someone. Do not spin your vehicle’s wheels faster
than 35 mph (55 km/h) when you are stuck, and do
not let anyone near a spinning wheel no matter what
the speed.
Tread Wear Indicators
Tread wear indicators are in the original equipment tires
to help you in determining when your tires should be
replaced.These indicators are molded into the bottom of the tread
grooves and will appear as bands when the tread depth
becomes 1/16 inch (2 mm). When the indicators appear
in 2 or more adjacent grooves, the tire should be replaced.
Many states have laws requiring tire replacement at this
point.
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Life of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
•Driving style
•Tire pressure
•Distance driven
WARNING!
Tires and spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have an accident result-
ing in serious injury or death.
Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
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WARNING!
•Do not use a tire, wheel size or rating other than that
specified for your vehicle. Some combinations of
unapproved tires and wheels may change suspen-
sion dimensions and performance characteristics,
resulting in changes to steering, handling, and brak-
ing of your vehicle. This can cause unpredictable
handling and stress to steering and suspension com-
ponents. You could lose control and have an accident
resulting in serious injury or death. Use only the tire
and wheel sizes with load ratings approved for your
vehicle.
•Never use a tire with a smaller load index or capacity,
other than what was originally equipped on your
vehicle. Using a tire with a smaller load index could
result in tire overloading and failure. You could lose
control and have an accident.
•Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.
Alignment and Balance
Poor suspension alignment may result in:
•Fast tire wear.
•Uneven tire wear, such as feathering and one-sided
wear.
•Vehicle pull to right or left.
Tires may also cause the vehicle to pull left or right.
Alignment will not correct this problem. See your autho-
rized dealer for proper diagnosis.
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Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
TIRE CHAINS
Certain models have sufficient tire-to-body clearance to
allow use of tire chains.Install chains on rear tires only.
Follow these recommendations to guard against damage
and excessive tire and chain wear:
•Do not install tire chains or traction devices on ve-
hicles with larger than P235/65R17 size tires. Tires
larger than this may not provide sufficient body
clearance with chains or other traction devices.
•Use SAE class “S” tire chains or traction devices only.
•Follow tire chain manufacturer’s instructions for
mounting chains.
•Install chains snugly and tighten after 1/2 mile (1 km)
of driving.
•Do notexceed 35 mph (56 km/h), unless otherwise
specified by the chain manufacturer.
•Drive cautiously, avoiding large bumps, potholes and
extreme driving maneuvers.
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, handling,
and braking functions. For these reasons, they wear at
unequal rates, and develop irregular wear patterns.
These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
aggressive tread designs such as those on On/Off Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride.
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Follow the recommended tire rotation frequency for your
type of driving found in the “Maintenance Schedules”
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.
NOTE:The Premium Tire Pressure Monitor System will
automatically locate the pressure values displayed in the
correct vehicle position following a tire rotation.
The suggested rotation method is the “forward-cross”
shown in the following diagram.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
The Tire Pressure Monitoring System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold tire pressure.
The tire pressure will vary with temperature by about 1
psi (7 kPa) for every 12°F (–11°C). This means that when
the outside temperature decreases, the tire pressure will
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decrease. Tire pressure should always be set based on
cold inflation tire pressure. This is defined as the tire
pressure after a vehicle has not been driven for more than
3 hours - and in outside ambient temperature.Refer to
the “Tires – General Information” in this section for
information on how to properly inflate the vehicle’s
tires.The tire pressure will also increase as the vehicle is
driven - this is normal and there should be no adjustment
for this increased pressure.
The TPM System will warn the driver of a low tire
pressure if the tire pressure falls below the low pressure
warning threshold for any reason, including low tem-
perature effects.
The TPM System will continue to warn the driver of low
tire pressure as long as the condition exists, and will not
turn off until the tire pressure is at or above recom-
mended cold tire pressure. Once the low tire pressure
warning has been illuminated, the tire pressure must beincreased to the recommended cold tire pressure in order
for the “Tire Pressure Monitoring Telltale Light” to be
turned off. The system will automatically update and the
“Tire Pressure Monitoring Telltale Light” will extinguish
once the updated tire pressures have been received. The
vehicle may need to be driven for up to 10 minutes above
15 mph (24 km/h) to receive this information.
For example, your vehicle has a recommended cold
(parked for more than 3 hours) tire pressure of 33 psi (227
kPa). If the ambient temperature is 68°F (20°C) and the
measured tire pressure is 28 psi (193 kPa), a temperature
drop to 20°F (-7°C) will decrease the tire pressure to
approximately 24 psi (165 kPa). This tire pressure is
sufficiently low enough to turn ON the “Tire Pressure
Monitoring Telltale Light.” Driving the vehicle may cause
the tire pressure to rise to approximately 28 psi (193 kPa),
but the “Tire Pressure Monitoring Telltale Light” will still
be ON. In this situation, the “Tire Pressure Monitoring
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