2012 JEEP GRAND CHEROKEE Owners Manual

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.
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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 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 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 read-
ings.
TIRE CHAINS (TRACTION DEVICES)
Use of traction devices require sufficient tire-to-body
clearance. Follow these recommendations to guard
against damage.
•Install on Rear Tires Only
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•Due to limited clearance, use SAE class “S” low profile
cables or traction devices only. Security Chain Com-
pany (SCC) Super Z6 #SZ 441 cables or equivalent are
recommended.
WARNING!
Using tires of different size and type (M+S, Snow)
between front and rear axles can cause unpredictable
handling. You could lose control and have a collision.
CAUTION!
To avoid damage to your vehicle or tires, observe the
following precautions:(Continued)
CAUTION! (Continued)
•Because of restricted traction device clearance be-
tween tires and other suspension components, it is
important that only traction devices in good con-
dition are used. Broken devices can cause serious
damage. Stop the vehicle immediately if noise
occurs that could indicate device breakage. Re-
move the damaged parts of the device before
further use.
•Install device as tightly as possible and then
retighten after driving about12mile (0.8 km).
•Do not exceed 30 mph (48 km/h).
•Drive cautiously and avoid severe turns and large
bumps, especially with a loaded vehicle.
•Do not drive for prolonged period on dry pave-
ment.(Continued)
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CAUTION! (Continued)
•Observe the traction device manufacturer ’s in-
structions on the method of installation, operating
speed, and conditions for use. Always use the
suggested operating speed of the device manufac-
turer ’s if it is less than 30 mph (48 km/h).
•Do not use traction devices on a compact spare tire.
SNOW TIRES
Some areas of the country require the use of snow tires
during the winter. All season tires can be indicated by the
M+S designation on the tire sidewall.
If you need snow tires, select tires equivalent in size and
type to the original equipment tires. Use snow tires only
in sets of four; failure to do so may adversely affect the
safety and handling of your vehicle.Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should
not be operated at sustained speeds over 75 mph
(120 km/h). For speeds above 75 mph (120 km/h) refer to
original equipment or an authorized tire dealer for
recommended safe operating speeds, loading and cold
tire inflation pressures.
While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
TIRE ROTATION RECOMMENDATIONS
The tires on the front and rear of your vehicle operate at
different loads and perform different steering, handling,
and braking functions. For these reasons, they wear at
unequal rates.
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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.
Refer to the “Maintenance Schedule” for the proper
maintenance intervals. 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 placard pressure.
The tire pressure will vary with temperature by about
1 psi (7 kPa) for every 12°F (6.5°C). This means that when
Tire Rotation
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the outside temperature decreases, the tire pressure will
decrease. Tire pressure should always be set based on
cold inflation tire pressure. This is defined as the tire
pressure after the vehicle has not been driven for at least
three hours, or driven less than 1 mile (1.6 km) after a
three-hour period.Refer to “Tires – General Informa-
tion” in “Starting and Operating” 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 TPMS 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 temperature
effects, or natural pressure loss through the tire.
The TPMS 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 recommended cold tire placard pressure. Once the low tire pressure
warning has been illuminated, the tire pressure must be
increased 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 20 minutes above
15 mph (24 km/h) to receive this information.
For example, your vehicle has a recommended cold
(parked for more than three hours) tire placard 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
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Light will still be ON. In this situation, the Tire Pressure
Monitoring Telltale Light will turn OFF only after the
tires have been inflated to the vehicle’s recommended
cold tire pressure value.
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
equipment that is not of the same size, type, and/or
style. Aftermarket wheels can cause sensor dam-
age. Do not use aftermarket tire sealants or balance
beads if your vehicle is equipped with a TPMS, as
damage to the sensors may result.(Continued)
CAUTION! (Continued)
•After inspecting or adjusting the tire pressure
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the valve
stem, which could damage the Tire Pressure Moni-
toring Sensor.
NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, or to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
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•The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure using an accurate tire gauge, even
if under-inflation has not reached the level to trigger
illumination of the Tire Pressure Monitoring Telltale
Light.
•Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Base 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.
NOTE:It is particularly important, for you to regularly
check the tire pressure in all of your tires, and to maintain
the proper pressure. The TPMS consists of the following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A low spare tire will not cause the Tire Pressure Moni-
toring Telltale Light to illuminate, a warning message to
appear, or the chime to sound. The Tire Pressure Monitoring Telltale Light will
illuminate in the instrument cluster, a “LOW TIRE
PRESSURE” message will display in the instru-
ment cluster for 5 seconds, and an audible chime will be
activated, when one or more of the four active road tire
pressures are low. Should this occur, you should stop as
soon as possible, check the inflation pressure of each tire
on your vehicle, and inflate each tire to the vehicle’s
recommended cold placard pressure value. The system
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