tire size JEEP WRANGLER 2008 JK / 3.G User Guide

Tire Sizing Chart
EXAMPLE:
Size Designation: P= Passenger car tire size based on U.S. design standards
....blank.... = Passenger car tire based on European design standards
LT = Light Truck tire based on U.S. design standards
T = Temporary Spare tire
31 = Overall Diameter in Inches (in)
215 = Section Width in Millimeters (mm)
65 = Aspect Ratio in Percent (%)
—Ratio of section height to section width of tire
10.5 = Section Width in Inches (in)
R = Construction Code
—Rmeans Radial Construction
—D means Diagonal or Bias Construction
15 = Rim Diameter in Inches (in)
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Tire Identification Number (TIN)
The TIN may be found on one or both sides of the tire
however the date code may only be on one side. Tires with
white sidewalls will have the full TIN including date codelocated on the white sidewall side of the tire. Look for the
TIN on the outboard side of black sidewall tires as mounted
on the vehicle. If the TIN is not found on the outboard side
then you will find it on the inboard side of the tire.
EXAMPLE:
DOT MA L9 ABCD 0301
DOT = Department of Transportation
—This symbol certifies that the tire is in compliance with the U.S. Department of Transportation tire
safety standards, and is approved for highway use.
MA = Code representing the tire manufacturing location (2 digits)
L9 = Code representing the tire size (2 digits)
ABCD = Code used by tire manufacturer (1 to 4 digits)
03 = Number representing the week in which the tire was manufactured (2 digits)
—03 means the 3rd week
01 = Number representing the year in which the tire was manufactured (2 digits)
—01 means the year 2001
—Prior to July 2000, tire manufacturers were only required to have 1 number to represent the year in
which the tire was manufactured. Example: 031 could represent the 3rd week of 1981 or 1991.
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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) total weight your vehicle can carry
3) tire size designed for your vehicle4) cold tire inflation pressures for the front, rear and
spare tires.
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 Tire and Loading
Information placard and the Vehicle Loading section of
this manual. Refer to “Vehicle Loading” in this section.
NOTE:
Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWRs) for the front and rear
axles must not be exceeded. For further information on
GAWRs, vehicle loading and trailer towing. Refer to
“Vehicle Loading” in this section.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX kg or XXX
Tire And Loading Information Placard
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lbs.” on the Tire and Loading Information placard. The
combined 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 “The combined weight of occu-
pants and cargo should never exceed XXX pounds” 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 “XXX”
amount equals 1,400 lbs (635 kg) and there will be five
150 lbs (68 kg) passengers in your vehicle, the amount of
available cargo and luggage load capacity is 650 lbs (295
kg) (since 5 x 150 = 750, and 1400 – 750 = 650 lbs (295 kg).5. Determine the combined weight of luggage and cargo
being loaded on the vehicle. That weight may not safely
exceed the available cargo and luggage load capacity
calculated in step 4.
6. If your vehicle will be towing a trailer, the load from
your trailer will be transferred to your vehicle. Consult
this manual to determine how this reduces the available
cargo and luggage load capacity of your vehicle.
NOTE:
The following table shows examples on how to
calculate total load, cargo/luggage and towing capacities
of your vehicle with varying seating configurations and
number and size of occupants. This table is for illustra-
tion purposes only and may not be accurate for the
seating and load carry capacity of your vehicle.
NOTE: For the following example the combined weight
of occupants and cargo should never exceed 865 lbs (392
kg).
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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 unmounted 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 (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion 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, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
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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 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.
• 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 an accident.
• Failure 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:
•Fast tire wear.
•Uneven tire wear, such as feathering and one-sided
wear.
•Vehicle 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.
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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
Install chains on rear tires only. Tire chains may be
installed on all models except the Sahara and Rubicon.
Follow these recommendations to guard against damage
and excessive tire and chain wear:
•Use chains on P225/75R16 tires only. P245/75R16,
P255/75R17, P255/70R18, and LT255/75R17 tires do
not provide adequate clearance.
•Use SAE class “S” tire chains or traction devices only.
•Chains must be the proper size for the vehicle, as
recommended by the chain manufacturer.
•Follow tire chain manufacturer’s instructions for
mounting chains.
•Install chains snugly and tighten after 0.6 mi (1 km) of
driving.
•Do notexceed 30 mph (48 km/h).
•Drive 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
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.
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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 equip-
ment that is not of the same size, type, and/or style.
Aftermarket 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.
CAUTION!
After inspecting or adjusting the tire pressure always
reinstall the valve stem cap. This will prevent mois-
ture and dirt from entering the valve stem, which
could damage the Tire Pressure Monitoring Sensor.
NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, nor 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, 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 TPM System 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 check the
tire pressure in all of your tires regularly and to maintain
the proper pressure. The Tire Pressure Monitor System (TPMS) consists of the
following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A tire pressure monitoring sensor is located in the spare
wheel if the vehicle is equipped with a matching full size
spare wheel and tire assembly. The matching full size
spare tire can be used in place of any of the four road
tires. A low spare tire will not cause the Tire Pressure
Monitoring Telltale Light to illuminate or the chime to
sound. The Tire Pressure Monitoring Telltale Light will
illuminate in the instrument cluster, and an au-
dible 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
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inflation pressure of each tire on your vehicle, and inflate
each tire to the vehicle’s recommended cold placard
pressure value. 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 10
minutes above 15 mph (25 km/h) to receive this infor-
mation.
The Tire Pressure Monitoring Telltale Light will flash on
and off for 75 seconds, and will remain on solid when a
system fault is detected. The system fault will also sound
a chime. If the ignition key is cycled, this sequence will
repeat, providing the system fault still exists. A system
fault can occur by any of the following scenarios:
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.3. Lots of snow or ice around the wheels or wheel
housings.
4. Using tire chains on the vehicle.
5. Using wheels/tires not equipped with TPM sensors.
NOTE:
If your vehicle is equipped with a matching
full-size spare wheel and tire assembly, it has a tire
pressure monitoring sensor, and can be monitored by the
Tire Pressure Monitoring System (TPMS). In the event
that the matching full-size spare tire is swapped with a
low pressure road tire, the next ignition key cycle will
still show the Tire Pressure Monitoring Telltale Light to
be ON, and a chime to sound. Driving the vehicle for up
to 10 minutes above 15 mph (25 km/h) will turn OFF the
Tire Pressure Monitoring Telltale Light as long as none of
the road tires are below the low pressure warning thresh-
old.
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