2007 JEEP GRAND CHEROKEE wheel size

Driver And Front Passenger Supplemental
Restraint Systems (SRS)This vehicle has airbags for both the driver and right
front passenger as a supplement to the seat belt restraint
systems. The driver's front airbag is mounted in the
steering wheel. The passenger side airbag is mounted in
the instrument panel, above the glove compartment. The
words SRS/AIRBAG are embossed on the airbag covers.
NOTE:The front airbags are certified to the Federal
regulations that allow less forceful deployment.
The front airbags have a multistage inflator design. This
may allow the airbag to have different rates of inflation
that are based on collision severity and occupant size.
Front Airbag Components
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²TheDriver and Passenger Airbag/Inflator Unitsare
located in the center of the steering wheel and the right
side of the instrument panel. When the ORC detects a
collision requiring the airbags, it signals the inflator
units. A large quantity of nontoxic gas is generated to
inflate the front airbags. Different airbag inflation rates
are possible, based on collision severity and occupant
size. The steering wheel hub trim cover and the upper
right side of the instrument panel separate and fold
out of the way as the bags inflate to their full size. The
bags fully inflate in about 50±70 milliseconds. This is
about half of the time it takes to blink your eyes. The
bags then quickly deflate while helping to restrain the
driver and front passenger.
The driver front airbag gas is vented through the vent
holes in the sides of the airbag. The passenger front
airbag gas is vented through the vent holes in the sides
of the airbag. In this way, the airbags do not interfere
with your control of the vehicle.²TheSide Impact SRS Side Curtain Airbagsare de-
signed to activate only in certain side or rollover
collisions. When the ORC (with side impact option)
detects a collision requiring the side curtain airbag to
inflate, it signals the inflators on the crash side of the
vehicle. A quantity of nontoxic gas is generated to
inflate the side curtain airbag. The inflating side cur-
tain airbag pushes the outside edge of the headliner
out of the way and covers the window. The airbag
inflates in about 30 milliseconds (about one quarter of
the time it takes to blink your eyes) with enough force
to injure you if you are not belted and seated properly,
or if items are positioned in the area where the side
curtain airbag inflates. This especially applies to chil-
dren. The side curtain airbag is only about 3
1¤2inches
(9 cm) thick when it is inflated.
²TheKnee Impact Bolstershelp protect the knees of
the driver and the front passenger, and position every-
one for the best interaction with the front airbag.
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WARNING!
²Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also, be certain to leave the transmis-
sion in P (Park). Failure to do so may allow the
vehicle to roll and cause damage or injury.
²Leaving children in a vehicle unattended is dan-
gerous for a number of reasons. A child or others
could be injured. Children should be warned not
to touch the parking brake or the gear selector
lever. Don't leave the keys in the ignition. A child
could operate power windows, other controls, or
move the vehicle.
²Be sure the parking brake is fully disengaged
before driving, failure to do so can lead to brake
problems due to excessive heating of the rear
brakes.
When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type and tires must be properly inflated to produce
accurate signals for the computer.
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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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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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