2008 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.
1 Ð Driver Airbag
2 Ð Passenger Airbag
3 Ð Knee BolsterTHINGS TO KNOW BEFORE STARTING YOUR VEHICLE 45
2

Also, the ORC turns on the ªAirbag Warning
Lightº for 6 to 8 seconds for a self-check
when the ignition is first turned on. After the
self-check, the ªAirbag Warning Lightº will
turn off. If the ORC detects a malfunction in any part
of the system, it turns on the ªAirbag Warning Lightº
either momentarily or continuously. A single chime
will sound if the light comes on again after initial start
up.
WARNING!
Ignoring the ªAirbag Warning Lightº in your instru-
ment panel could mean you won't have the airbags to
protect you in a collision. If the light does not come
on, stays on after you start the vehicle, or if it comes
on as you drive, have the airbag system checked right
away.
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.
50 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

of reasons, including the installation of replacement or
alternate tires or wheels on the vehicle that prevent the
TPMS from functioning properly. Always check the
TPMS malfunction telltale after replacing one or more
tires or wheels on your vehicle to ensure that the replace-
ment or alternate tires and wheels allow the TPMS to
continue to function properly.CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system opera-
tion or sensor damage may result when using re-
placement equipment that is not of the same size,
type, and/or style. After-market wheels can cause
sensor damage. Do not use aftermarket tire sealants
or balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result.
13. Temperature Gauge
The temperature gauge shows engine coolant tempera-
ture. Any reading within the normal range indicates that
the engine cooling system is operating satisfactorily.
178 UNDERSTANDING YOUR INSTRUMENT PANEL

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.
254 STARTING AND OPERATING

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 suspension
dimensions and performance characteristics, result-
ing in changes to steering, handling, and braking of
your vehicle. This can cause unpredictable handling
and stress to steering and suspension components.
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 ad-
equate 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
readings.
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.
274 STARTING AND OPERATING