JEEP GRAND CHEROKEE 2007 WK / 3.G SRT Owners Manual

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
12É F (7É C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage especially in
the winter.
Example: If garage temperature = 68É F (20É C) and the
outside temperature = 32É F (0É C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12É F (7É 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.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.
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WARNING!
High speed driving with your vehicle under maxi-
mum 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.
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Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle's wheels above 35 mph (55 km/h).
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
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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.
Life of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
²Driving style
²Tire pressure
²Distance driven
WARNING!
All tires should be replaced after six years, regard-
less of the remaining tread. Failure to follow this
warning can result in sudden tire failure. You could
lose control and have an accident resulting in serious
injury.
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.
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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.WARNING!
²Do 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.
²Never 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.
²Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
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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:
²Fast tire wear.
²Uneven tire wear, such as feathering and one-sided
wear.
²Vehicle 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.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 ROTATION RECOMMENDATIONS
Do not rotate the tires as the wider rear tires will not fit
on the front of the vehicle.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
Premium System
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim mounted electronic sensors to
monitor tire pressure levels. Sensors mounted to each
wheel as part of the valve stem transmit tire pressure
readings to the Receiver Module. The wheel sensors
monitor tire pressure, and status for all four active road
tires.
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NOTE:It is particularly important, for you to check the
tire pressure in all of your tires regularly and to maintain
the proper pressure.
The ªTire Pressure Monitoring Telltale Lightº will
illuminate in the instrument cluster, and an au-
dible chime will be activated when one or more
tire pressures is low. The ªTire Pressure Monitoring
Telltale Lightº will flash on and off for 60 seconds when
a system fault is detected. The flash cycle will repeat
every ten minutes or until the fault condition is removed
and reset.
The Tire Pressure Monitoring System (TPMS) consists of
the following components:
²Receiver Module
²4 Wheel Sensors
²3 Wheel Sensor Trigger Modules
²Tire Pressure Monitoring System Display Messages in
the EVIC
²Tire Pressure Monitoring Telltale Light
The system consists of tire pressure monitoring sensors
attached to each wheel through the valve stem mounting
hole, a central receiver module, Wheel Sensor Trigger
Modules mounted in three of the four wheel wells,
various Tire Pressure Monitoring System Display Mes-
sages in the EVIC, and a ªTire Pressure Monitoring
Telltale Light.º
NOTE:For vehicles with optional wheel/tire sizes and
significantly different tire placard pressures, the placard
pressure value and the low-pressure threshold value is
re-programmable at your authorized dealer to accommo-
date the customer selected wheel/tire combinations rec-
ommended by DaimlerChrysler Corporation.
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The following9warnings9will cause a text message to be
displayed, an audible chime to sound, and the ªTire
Pressure Monitoring Telltale Lightº to illuminate. The
audible chime will occur once every ignition cycle for
each9warning9detected. The ªTire Pressure Monitoring
Telltale Lightº will illuminate continuously (solid) and
shall remain illuminated until the warning condition is
removed/reset.
When the appropriate conditions exist, the Electronic
Vehicle Information Center (EVIC) displays the following
messages.LEFT FRONT, LEFT REAR, RIGHT FRONT,
RIGHT REAR LOW PRESSURE
One or more of these messages will be displayed in the
EVIC if a low tire pressure condition exists in one or more
tires.
Inspect all tires for proper inflation pressure, once the
proper tire pressure has been set, the TPMS will reset
automatically when the vehicle has been driven for at
least 2 minutes at or above 15 mph (24 km/h).
CHECK TPM SYSTEM
See your authorized dealer when this message appears in
the EVIC. This message indicates that a system fault
condition has been detected.
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CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement equip-
ment that is not of the same size, type, and/or style.
After-market wheels can cause sensor damage. Do
not use tire sealant from a can, or balance beads if
your vehicle is equipped with a TPMS, as damage to
the sensors may result.
CAUTION!
After inspecting or adjusting the tire pressure al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage the wheel rim sensor.
NOTE:
²The TPMS can inform the driver of a low tire pressure
condition.
²The TPMS is not intended to replace normal tire care
and maintenance, nor to provide warning of a tire
failure or condition.
²The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
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General Information
This device complies with part 15 of the FCC rules and
RSS 210 of Industry Canada. Operation is subject to the
following conditions:
²This device may not cause harmful interference.
²This device must accept any interference received,
including interference that may cause undesired op-
eration.
The tire pressure sensors are covered under one of the
following licenses:
United States.....................KR5S120123
Canada........................2671-S120123
FUEL REQUIREMENTS
Your vehicle is designed to meet all emis-
sion regulations and provide excellent fuel
economy when using high quality pre-
mium unleaded gasoline having an octane
rating of 91 or higher.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of ªpremiumº gasoline
before considering service for the vehicle.
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