2013 JEEP GRAND CHEROKEE wheel size

turns on the Air Bag Warning Light, either momentarily
or continuously. A single chime will sound if the light
comes on again after initial startup.
It also includes diagnostics that will illuminate the instru-
ment cluster Air Bag Warning Light if a malfunction is
noted that could affect the air bag system. The diagnos-
tics also record the nature of the malfunction.
WARNING!
Ignoring the Air Bag Warning Light in your instru-
ment panel could mean you won’t have the air bags
to protect you in a collision. If the light does not come
on as a bulb check when the ignition is first turned
on, stays on after you start the vehicle, or if it comes
on as you drive, have an authorized dealer service the
air bag system immediately.
Driver And Passenger Advanced Front Air Bag
Inflator Units
The Driver and Passenger Advanced Front Air Bag
Inflator Units are located in the center of the steering
wheel and on the right side of the instrument panel.
When the ORC detects a collision requiring the Ad-
vanced Front Air Bags, it signals the inflator units. A large
quantity of non-toxic gas is generated to inflate the
Advanced Front Air Bags. Different air bag inflation rates
are possible, based on several factors, including the
collision type and severity. The steering wheel hub trim
cover and the upper right side of the instrument panel
separate and fold out of the way as the air bags inflate to
their full size. The air bags fully inflate in about 50 to
70 milliseconds. This is about half of the time it takes to
blink your eyes. The air bags then quickly deflate while
helping to restrain the driver and front passenger.
2
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 77

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. Aftermarket 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.
12. Park/Headlight ON Indicator — If Equipped
This indicator will illuminate when the park
lights or headlights are turned on.13. Seat Belt Reminder Light
When the ignition switch is first turned to the
ON/RUN position, this light will turn on for four
to eight seconds as a bulb check. During the bulb
check, if the driver’s seat belt is unbuckled, a chime will
sound. After the bulb check or when driving, if the driver
or front passenger seat belt remains unbuckled, the Seat
Belt Indicator Light will flash or remain on continuously.
Refer to “Occupant Restraints” in “Things To Know
Before Starting Your Vehicle” for further information.
14. Brake Warning Light
This light monitors various brake functions,
including brake fluid level and parking brake
application. If the brake light turns on it may
indicate that the parking brake is applied, that
the brake fluid level is low, or that there is a problem with
the anti-lock brake system reservoir.
308 UNDERSTANDING YOUR INSTRUMENT PANEL

TIRES — GENERAL INFORMATION.........518
▫Tire Pressure........................518
▫Tire Inflation Pressures.................519
▫Tire Pressures For High Speed Operation. . . .521
▫Radial Ply Tires......................521
▫All Season Tires – If Equipped............521
▫Summer Or Three Season Tires – If Equipped. .522
▫Snow Tires..........................522
▫Spare Tire Matching Original Equipped Tire And
Wheel – If Equipped...................523
▫Compact Spare Tire – If Equipped.........523
▫Full Size Spare – If Equipped.............524
▫Limited-Use Spare – If Equipped..........524▫Tire Spinning........................525
▫Tread Wear Indicators..................526
▫Life Of Tire.........................526
▫Replacement Tires.....................527
TIRE CHAINS (TRACTION DEVICES).......528
TIRE ROTATION RECOMMENDATIONS.....530
TIRE PRESSURE MONITOR SYSTEM (TPMS) . .531
▫Base System.........................534
▫Premium System – If Equipped............536
▫General Information...................540
FUEL REQUIREMENTS..................541
▫3.6L Engine – If Equipped...............541
▫5.7L Engine – If Equipped...............541
436 STARTING AND OPERATING

ABS and Traction Control, provides resistance to any
wheel that is slipping to allow additional torque transfer
to wheels with traction.
NOTE:The Quadra-Trac I® system is not appropriate
for conditions where 4WD LOW range is recommended.
Refer to “Off-Road Driving Tips” in “Starting and Oper-
ating” for further information.
Quadra-Trac II® Operating Instructions/
Precautions – If Equipped
The Quadra-Trac II® transfer case is fully automatic in
the normal driving 4WD AUTO mode. The Quadra-Trac
II® transfer case provides three mode positions:
•4WD HI
•NEUTRAL
•4WD LOWThis transfer case is fully automatic in the 4WD HI mode.
When additional traction is required, the 4WD LOW
position can be used to lock the front and rear driveshafts
together and force the front and rear wheels to rotate at
the same speed. The 4WD LOW position is intended for
loose, slippery road surfaces only. Driving in the 4WD
LOW position on dry, hard-surfaced roads may cause
increased tire wear and damage to driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 4WD HI
position at a given road speed. Take care not to overspeed
the engine and do not exceed 25 mph (40 km/h).
Proper operation of four-wheel drive vehicles depends
on tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
468 STARTING AND OPERATING

Spare Tire Matching Original Equipped Tire And
Wheel – If Equipped
Your vehicle may be equipped with a spare tire and
wheel equivalent in look and function to the original
equipment tire and wheel found on the front or rear axle
of your vehicle. This spare tire may be used in the tire
rotation for your vehicle. If your vehicle has this option
refer to an authorized tire dealer for the recommended
tire rotation pattern.
If your vehicle is not equipped with an original equip-
ment tire and wheel as a spare, a non-matching tempo-
rary emergency use spare may be equipped with your
vehicle. Temporary use spares are engineered to be used
only with your vehicle. Your vehicle may be equipped
with one of the following types of non-matching tempo-
rary use spares; compact, full size, or limited-use. Do not
install more than one non-matching temporary use spare
tire/wheel on the vehicle at any given time.
CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with a
compact, full size or limited-use temporary spare
installed. Damage to the vehicle may result.
Compact Spare Tire – If Equipped
The compact spare is for temporary emergency use only.
You can identify if your vehicle is equipped with a
compact spare by looking at the spare tire description on
the Tire and Loading Information Placard located on the
driver ’s side door opening or on the sidewall of the tire.
Compact spare tire descriptions begin with the letter “T”
or “S” preceding the size designation. Example: T145/
80D18 103M.
T, S = Temporary Spare Tire5
STARTING AND OPERATING 523

Since this tire has limited tread life the original equip-
ment tire should be repaired (or replaced) and reinstalled
on your vehicle at the first opportunity.
Do not install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare tire.
Do not install more than one compact spare tire and
wheel on the vehicle at any given time.
WARNING!
Compact spares are for temporary emergency use
only. With these spares, do not drive more than
50 mph (80 km/h). Temporary use spares have limited
tread life. When the tread is worn to the tread wear
indicators, the temporary use spare tire needs to be
replaced. Be sure to follow the warnings, which
apply to your spare. Failure to do so could result in
spare tire failure and loss of vehicle control.
Full Size Spare – If Equipped
The full size spare is for temporary emergency use only.
This tire may look like the original equipped tire on the
front or rear axle of your vehicle, but it is not. This spare
tire may have limited tread life. When the tread is worn
to the tread wear indicators, the temporary use full size
spare tire needs to be replaced. Since it is not the same as
your original equipment tire, replace (or repair) the
original equipment tire and reinstall on the vehicle at the
first opportunity.
Limited-Use Spare – If Equipped
The limited-use spare tire is for temporary emergency
use only. This tire is identified by a label located on the
limited-use spare wheel. This label contains the driving
limitations for this spare. This tire may look like the
original equipped tire on the front or rear axle of your
vehicle, but it is not. Installation of this limited-use spare
tire affects vehicle handling. Since it is not the same as
524 STARTING AND OPERATING

WARNING!
Tires and the 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 a collision resulting
in serious injury or death.
Keep dismounted 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. (Refer to the paragraph on“Tread Wear Indicators”). Refer to the “Tire and Loading
Information” placard for the size designation of your tire.
The Load Index and Speed Symbol for your tire will be
found on the original equipment tire sidewall. See the
Tire Sizing Chart example found in the Tire Safety
Information section of this manual for more information
relating to the Load Index and Speed Symbol of a tire.
It is recommended to replace the two front tires or two
rear tires as a pair. Replacing just one tire can seriously
affect your vehicle’s handling. If you ever replace a
wheel, make sure that the wheel’s specifications match
those of the original wheels.
It is recommended you contact your original equipment
or an authorized tire dealer with any questions you may
have on tire specifications or capability. Failure to use
equivalent replacement tires may adversely affect the
safety, handling, and ride of your vehicle.
5
STARTING AND OPERATING 527

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 sus-
pension dimensions and performance characteris-
tics, resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpredict-
able handling and stress to steering and suspen-
sion components. You could lose control and have
a collision 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 a collision.
(Continued)
WARNING!(Continued)
•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 readings.
TIRE CHAINS (TRACTION DEVICES)
Use of traction devices require sufficient tire-to-body clear-
ance. Follow these recommendations to guard against dam-
age.
•Traction device must be of proper size for the tire, as
recommended by the traction device manufacturer.
•Install on Rear Tires Only
528 STARTING AND OPERATING