tire pressure JEEP COMMANDER 2008 1.G User Guide

²European Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letter9P9is absent from this tire
size designation. Example: 215/65R15 96H
²LT (Light Truck)-Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters ªLTº that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
²Temporary Spare tires are high-pressure compact
spares designed for temporary emergency use only.
Tires designed to this standard have the letter ªTº
molded into the sidewall preceding the size designa-
tion. Example: T145/80D18 103M.
²High Flotation tire sizing is based on U.S. design
standards and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
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EXAMPLE:
Service Description:
95= Load Index
ÐA numerical code associated with the maximum load a tire can carry.
H= Speed Symbol
ÐA symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions.
ÐThe maximum speed corresponding to the Speed Symbol should only be achieved un-
der specified operating conditions (i.e. tire pressure, vehicle loading, road conditions, and
posted speed limits).
Load Identification:
(....blank....(= Absence of any text on sidewall of the tire indicates a Standard Load (SL) Tire
Extra Load (XL)= Extra Load (or Reinforced) Tire
Light Load= Light Load Tire
C,D,E= Load range associated with the maximum load a tire can carry at a specified pressure
Maximum LoadÐ Maximum Load indicates the maximum load this tire is designed to carry.
Maximum PressureÐ
Maximum Pressure indicates the maximum permissible cold tire inflation pressure for this tire.
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Tire Loading and Tire Pressure
Tire Placard Location
NOTE:The proper cold tire inflation pressure is listed
on either the face of the driver's door or the driver's side
ªBº pillar.
Tire and Loading Information Placard
This placard tells you important information about the:
1) number of people that can be carried in the vehicle
2) the total weight your vehicle can carry
3) the tire size designed for your vehicle
4) the cold tire inflation pressures for the front, rear,
and spare tires.
Tire Placard Location
Tire and Loading Information
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Loading
The vehicle maximum load on the tire must not exceed
the load carrying capacity of the tire on your vehicle. You
will not exceed the tire's load carrying capacity if you
adhere to the loading conditions, tire size, and cold tire
inflation pressures specified on the ªTire and Loading
Informationº placard and in the ªVehicle Loadingº sec-
tion of this manual.
NOTE:Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWR's) for the front and rear
axles must not be exceeded. For further information on
GAWR's, vehicle loading, and trailer towing, refer to the
ªVehicle Loadingº section of this manual.
To determine the maximum loading conditions of your
vehicle, locate the statement ªThe combined weight of
occupants and cargo should never exceed XXX kg or XXX
lbs.º on the Tire and Loading Information placard. Thecombined weight of occupants, cargo/luggage and
trailer tongue weight (if applicable) should never exceed
the weight referenced here.
Steps for Determining Correct Load Limit
1. Locate the statement ªThe combined weight of occu-
pants and cargo should never exceed XXX poundsº on
your vehicle's placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and pas-
sengers from XXX kilograms or XXX pounds.
4. The resulting figure equals the available amount of
cargo and luggage load capacity. For example, if ªXXXº
amount equals 1400 lbs. and there will be five 150 lb.
passengers in your vehicle, the amount of available cargo
and luggage load capacity is 650 lbs. (since 5 x 150 = 750,
and 1400 ± 750 = 650 lbs.)
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WARNING!
Overloading of your tires is dangerous. Overloading
can cause tire failure, affect vehicle handling, and
increase your stopping distance. Use tires of the
recommended load capacity for your vehicle. Never
overload them.
TIRES Ð GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the safe and
satisfactory operation of your vehicle. Three primary
areas are affected by improper tire pressure:1. SafetyÐ
WARNING!
²Improperly inflated tires are dangerous and can cause
accidents.
²Under inflation increases tire flexing and can result in
tire failure.
²Over inflation reduces a tire's ability to cushion
shock. Objects on the road and chuckholes can cause
damage that result in tire failure.
²Unequal tire pressures can cause steering problems.
You could lose control of your vehicle.
²Over inflated or under inflated tires can affect vehicle
handling and can fail suddenly, resulting in loss of
vehicle control.
²Unequal tire pressures from one side of the vehicle to
the other can cause the vehicle to drift to the right or left.
²Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.
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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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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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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 CHAINS
Only models fitted with 235/65R17XL (extra load) tires
have sufficient tire-to-body clearance to allow use of tire
chains.Install chains on rear tires only.Follow these
recommendations to guard against damage and exces-
sive tire and chain wear:
²Do not install tire chains or traction devices on ve-
hicles with larger than 235/65R17XL size tires. Tires
larger than this may not provide sufficient body
clearance with chains or other traction devices.
²Manufacturer recommends a cold inflation pressure of
38 psi (262 kPa) when using 235/65R17XL size tires for
this vehicle.
²Use SAE class ªSº tire chains or traction devices only.
²Follow tire chain manufacturer's instructions for
mounting chains.
²Install chains snugly and tighten after 1/2 mile (1 km)
of driving.
²Do notexceed 30 mph (48 km/h), unless otherwise
specified by the chain manufacturer.
²Drive cautiously, avoiding large bumps, potholes and
extreme driving maneuvers.
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, handling,
and braking functions. For these reasons, they wear at
unequal rates, and develop irregular wear patterns.
These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
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