tires JEEP WRANGLER 2009 User Guide

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 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
refer to your original equipment or contact an authorized
tire dealer with any questions you may have on tire
specifications or capability.
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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. 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 mile (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.
Refer to the “Maintenance Schedule” in Section 8 for the
proper maintenance intervals. More frequent rotation is
permissible if desired. The reasons for any rapid or
unusual wear should be corrected prior to rotation being
performed.
350 STARTING AND OPERATING

off until the tire pressure is at or above recommended
cold placard pressure. Once the “Tire Pressure Monitor-
ing Telltale Light” has been illuminated, the tire pressure
must be increased to the recommended cold placard
pressure in order for the “Tire Pressure Monitoring
Telltale Light” to be turned OFF. The system will auto-
matically 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 (25 km/h) to
receive this information.
For example, your vehicle may have a recommended
cold (parked for more than three hours) air pressure of
35 psi (241 kPa). If the ambient temperature is 68°F (20°C)
and the measured tire pressure is 30 psi (207 kPa), a
temperature drop to 20°F (-7°C) will decrease the tire
pressure to approximately 26 psi (179 kPa). This tire
pressure is sufficiently low enough to turn ON the “Tire
Pressure Monitoring Telltale Light.” Driving the vehiclemay cause the tire pressure to rise to approximately
30 psi (207 kPa), but the “Tire Pressure Monitoring
Telltale 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 recom-
mended cold placard pressure value.

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 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
20 minutes above 15 mph (25 km/h) to receive this
information.
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.

vehicle in place of the spare tire, the TPMS will update
automatically and the “Tire Pressure Monitoring Tell-
tale Light” will turn OFF, as long as no tire pressure is
below the low-pressure warning limit in any of the
four active road tires. The vehicle may need to be
driven for up to 20 minutes above 15 mph (25 km/h)
in order for the TPMS to receive this information.
General Information
This device complies with part 15 of the FCC rules and
RSS 210 of Industry Canada. Operation is subject to the
following conditions:
•This device may not cause harmful interference.
•This device must accept any interference received,
including interference that may cause undesired
operation.The tire pressure sensors are covered under one of the
following licenses:
United States
..................... KR5S120123
Canada ........................ 2671-S120123
FUEL REQUIREMENTS
All engines are designed to meet all emis-
sions regulations and provide excellent
fuel economy and performance when us-
ing high quality unleaded “regular” gaso-
line having an octane rating of 87. The use
of premium gasoline is not recommended,
as it will not provide any benefit over regular gasoline in
these engines.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage, and immediate service is
required.

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’s 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 ve-
hicle’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.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight
values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
Loading
The actual total weight and the weight of the front and
rear of your vehicle at the ground can best be determined
by weighing it when it is loaded and ready for operation.
364 STARTING AND OPERATING

WARNING! (Continued)
4. Tongue weight rating for the trailer hitch utilized
(This requirement may limit the ability to always
achieve the 10% to 15% range of tongue weight as a
percentage of total trailer weight).
Towing Requirements — Tires

Do not attempt to tow a trailer while using a compact
spare tire.
Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires–General Information” in this section for proper
tire inflation procedures.
Check the trailer tires for proper tire inflation pres-
sures before trailer usage.
Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires–General Infor-
mation” in this section for the proper inspection pro-
cedure.
When replacing tires, refer to “Tires–General Informa-
tion” in this section for proper tire replacement proce-
dures. Replacing tires with a higher load carrying
capacity will not increase the vehicle’s GVWR and
GAWR limits.
Towing Requirements — Trailer Brakes

Do not interconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
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WARNING! (Continued)
•Do not let anyone sit in the vehicle when it is on a
jack.
•Do not get under the vehicle when it is on a jack.
•Only use the jack in the positions indicated and
for lifting this vehicle during a tire change.
•If working on or near a roadway, be extremely
careful of motor traffic.
•To assure that spare tires, flat or inflated, are
securely stowed, spares must be stowed with the
valve stem facing the ground.
•Turn on the Hazard Warning flasher.1. Remove the spare tire, jack and tools from the stored
location.
2. Loosen (but do not remove) the wheel lug nuts by
turning them to the left one turn while the wheel is still
on the ground.
3. Assemble the jack and jacking tools. Connect the jack
handle driver to the extension, then to the lug wrench.
4. Operate the jack from the front or the rear of the
vehicle. Place the jack under the axle tube, as shown.
Do
not raise the vehicle until you are sure the jack is fully
engaged.

Selection of Lubricant
Use only manufacturer’s recommended fluid. Refer to
“Fluids, Lubricants, and Genuine Parts” in this section
for the correct fluid type.
Maintenance After Off-Road Driving
After extended operation in mud, sand or water, or
similar dirty conditions, have your brake drums, brake
linings, and axle joints inspected and cleaned as soon as
possible. This will prevent any abrasive material from
causing excessive wear or unpredictable braking action.
Following off-road usage, completely inspect the under-
body of your vehicle. Check the tires, body structure,
steering, suspension and exhaust system for damage.
Check the threaded fasteners for looseness, particularly
on the chassis, drivetrain components, steering and sus-
pension. Retighten, if required, to torque values specified
in the Service Manual. Also check for accumulations of
vegetation or brush that could become a fire hazard, orconceal damage to fuel lines, brake hoses, axle pinion
seals, and propeller shafts. Check the air conditioning
drain tube on the lower dash wall in the engine compart-
ment for mud or debris, and clean as required. A plugged
tube will adversely affect air conditioning performance.

Temperature Grades
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation of heat
and its ability to dissipate heat, when tested under
controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire failure. The
grade C corresponds to a level of performance, which all
passenger car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B and A repre-
sent higher levels of performance on the laboratory test
wheel, than the minimum required by law.