2008 JEEP LIBERTY inflation pressure

2. EconomyÐ
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under inflation also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle StabilityÐ
Proper tire inflation contributes to a comfortable ride.
Over inflation produces a jarring and uncomfortable ride.
Both under inflation and over inflation affect the stability
of the vehicle and can produce a feeling of sluggish
response or over responsiveness in the steering.
Unequal tire pressures can cause erratic and unpredict-
able steering response.
Unequal tire pressure from side to side may cause the
vehicle to drift left or right.Tire Inflation Pressures
The proper cold tire inflation pressure is listed on either
the face of the driver's door or the driver's side ªBº pillar.
The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to
Tire Placard Location
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check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
ªcold tire inflation pressure.º Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least 3 hours, or driven less than 1 mile
(1 km) after a 3 hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire sidewall.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.
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5

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.
WARNING!
High speed driving with your vehicle at or above
maximum 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.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle's wheels above 35 mph (55 km/h).
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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!
Tires and 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 an accident 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
ªTread Wear Indicatorsº). Refer to the ªTire and Loading
Informationº 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, handling, and ride of your vehicle. We recommend
that you contact your original equipment or an autho-
rized tire dealer with any questions you may have on tire
specifications or capability.
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TIRE PRESSURE MONITOR SYSTEM (TPMS) Ð IF
EQUIPPED
²
The Tire Pressure Monitor System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold placard pressure.
²The tire pressure will vary with temperature by about
1 psi (6.9 kPa) for every 12ÉF (6.5ÉC). This means that
when the outside temperature decreases, the tire pres-
sure 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 3 hours, or driven less than 1 mile (1 km)
after a 3 hour period. The cold tire inflation pressure
must not exceed the maximum inflation pressure
molded into the tire sidewall. Refer to the ªTires ±
General Informationº in this section for information
on how to properly inflate the vehicle's tires. The tirepressure will also increase as the vehicle is driven - this
is normal and there should be no adjustment for this
increased pressure.
²The TPM System will warn the driver of a low tire
pressure if the tire pressure falls below the low-
pressure warning limit for any reason, including low
temperature effects and natural pressure loss through
the tire.
²The TPM System 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
the recommended cold placard pressure. Once the low
tire pressure warning (Tire Pressure Monitoring Tell-
tale Light) illuminates, you must increase the tire
pressure to the recommended cold placard pressure in
order for the Tire Pressure Monitoring Telltale Light to
turn off. The system will automatically update and the
Tire Pressure Monitoring Telltale Light will turn off
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NOTE:
²The TPMS is not intended to replace normal tire care
and maintenance, or 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.
²Driving 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.
²The 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 pressure
gauge, even if under-inflation has not reached the
level to trigger illumination of the Tire Pressure Moni-
toring Telltale light.
²Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Base System Ð If Equipped
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 check the
tire pressure in all of the tires on your vehicle monthly
and to maintain the proper pressure.
The TPMS consists of the following components:
²Receiver Module
²4 Tire Pressure Monitoring Sensors
²Tire Pressure Monitoring Telltale Light
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The matching full size spare wheel and tire assembly (if
equipped) has a tire pressure monitoring sensor. The
matching full size spare can be used in place of any of the
four road tires. The TPMS will only monitor the pressure
in the full size spare when it is used in place of a road tire.
Otherwise, a spare with a pressure below the low-
pressure limit will not cause the Tire Pressure Monitoring
Telltale Light to illuminate or the chime to sound.
Tire Pressure Monitoring Low Pressure Warnings
The Tire Pressure Monitoring Telltale Light will
illuminate in the instrument cluster and a chime
will sound when tire pressure is low in one or
more of the four active road tires. 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. Once the system receives the updated tire pres-
sures, the system will automatically update and the Tire
Pressure Monitoring Telltale Light will turn off. Thevehicle may need to be driven for up to 10 minutes above
15 mph (25 km/h) in order for the TPMS to receive this
information.
Check TPMS Warning
When a system fault is detected, the Tire Pressure Moni-
toring Telltale Light will flash on and off for 75 seconds
and then remain on solid. The system fault will also
sound a chime. If the ignition key is cycled, this sequence
will repeat, providing the system fault still exists. The
Tire Pressure Monitoring Telltale Light will turn off when
the fault condition no longer exists. A system fault can
occur due to any of the following:
1. Jamming due to electronic devices or driving next to
facilities emitting the same Radio Frequencies as the TPM
sensors.
2. Installing some form of aftermarket window tinting
that affects radio wave signals.
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5

Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options, trailer
tongue weight, and cargo. The label also specifies maxi-
mum capacities of front and rear axle systems (GAWR).
Total load must be limited, so GVWR, and front and rear
GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the
driver, all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires, or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle's GVWR.
Tire Size
The tire size on the Label represents the actual tire size on
your vehicle. Replacement tires must be equal to the load
capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
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