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EXAMPLE:
Service Description:
95= Load Index
— A numerical code associated with the maximum load a tire can carry
H= Speed Symbol
— A symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions
— The maximum speed corresponding to the speed symbol should only be achieved under
specified operating conditions (i.e., tire pressure, vehicle loading, road conditions, and
posted speed limits)
Load Identification:
....blank....= Absence of any text on the sidewall of the tire indicates a Standard Load (SL) tire
Extra Load (XL)= Extra load (or reinforced) tire
Light Load (LL)= Light load tire
C, D, E, F, G= Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load— Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure— Maximum pressure indicates the maximum permissible cold tire inflation pressure for
this tire
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These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes 1/16 in (2 mm). When the tread is worn to the
tread wear indicators, the tire should be replaced.
Many states have laws requiring tire replacement at this
point.
Life Of Tire
The service life of a tire is dependent upon varying
factors including, but not limited to:
•Driving style
•Tire pressure
•Distance 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 a collision 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
“Tread Wear Indicators”). Refer to the “Tire and Loading
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CAUTION! (Continued)
•When replacing a flat, the spare tire may have to
be remounted on the rim or installed at a different
location to maintain the correct placement of the
tire on the wheel relative to the tire/wheel position
on the vehicle. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires will maintain proper position.
FUEL REQUIREMENTS
The 5.7L engine is designed to meet all
emissions regulations and provide satisfac-
tory fuel economy and performance when
using high-quality unleaded gasoline hav-
ing an octane range of 87 to 89. The manu-
facturer recommends the use of 89 octanefor optimum performance. 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.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of “regular” gasoline be-
fore considering service for the vehicle.
Over 40 auto manufacturers worldwide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance
and durability for your vehicle. We recommend the use
of gasolines that meet the WWFC specifications if they
are available.
5
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Materials Added To Fuel
All gasolines sold in the United States are required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions and would result in unnecessary cost. There-
fore, you should not have to add anything to the fuel.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine perfor-
mance, damage the emission control system.
(Continued)
CAUTION! (Continued)
•An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune
or malfunctioning and may require immediate
service. Contact your authorized dealer for service
assistance.
•When pulling a heavy load or driving a fully-
loaded vehicle when the humidity is low and the
temperature is high, use a premium unleaded fuel
to help prevent spark knock. If spark knock per-
sists, lighten the load, or engine piston damage
may result.
(Continued)
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HAZARD WARNING FLASHERS
The Hazard Warning flasher switch is located on the
upper switch bank just below the radio.
Press the switch to turn on the Hazard Warning
flasher. When the switch is activated, all directional
turn signals will flash on and off to warn oncoming
traffic of an emergency. Press the switch a second time to
turn off the Hazard Warning flashers.
This is an emergency warning system and it should not
be used when the vehicle is in motion. Use it when your
vehicle is disabled and it is creating a safety hazard for
other motorists.
When you must leave the vehicle to seek assistance, the
Hazard Warning flashers will continue to operate even
though the ignition is placed in the OFF position.
NOTE:With extended use the Hazard Warning flashers
may wear down your battery.
JACKING AND TIRE CHANGING
WARNING!
•Do not attempt to change a tire on the side of the
vehicle close to moving traffic, pull far enough off
the road to avoid the danger of being hit when
operating the jack or changing the wheel.
•Being under a jacked-up vehicle is dangerous. The
vehicle could slip off the jack and fall on you. You
could be crushed. Never put any part of your body
under a vehicle that is on a jack.
•Never start or run the engine while the vehicle is
on a jack. If you need to get under a raised vehicle,
take it to a service center where it can be raised on
a lift.
(Continued)
380 WHAT TO DO IN EMERGENCIES
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WARNING! (Continued)
•The jack is designed to use as a tool for changing
tires only. The jack should not be used to lift the
vehicle for service purposes. The vehicle should
be jacked on a firm level surface only. Avoid ice or
slippery areas.
3500 Models — If Equipped
The jack and jack tools are stored under the front
passenger seat. Lift the flap on the side of the seat for
access.
Remove the jack and tools by removing the wing bolt and
sliding the assembly from under the seat.
Jack Location6
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WARNING!
After using the jack and tools, always reinstall them
in the original carrier and location. While driving
you may experience abrupt stopping, rapid accelera-
tion, or sharp turns. A loose jack, tools, bracket or
other objects in the vehicle may move around with
force, resulting in serious injury.
4500/5500 Models
These vehicles do not come equipped with a jack.
NOTE:Jacking and tire changing on 4500/5500 models
should be performed by an authorized dealer, or knowl-
edgeable service personnel with the appropriate heavy
duty equipment, like a tire service company.
Preparations For Jacking
1. Park the vehicle on a firm, level surface. Avoid ice or
slippery areas.
WARNING!
Do not attempt to change a tire on the side of the
vehicle close to moving traffic, pull far enough off
the road to avoid the danger of being hit when
operating the jack or changing the wheel.
2. Turn on the Hazard Warning flasher.
3. Set the parking brake.
4. Place the shift lever into PARK (automatic transmis-
sion) or REVERSE (manual transmission). On 4-Wheel
drive vehicles, shift the transfer case to the “4L” position.
5. Turn OFF the ignition.
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4. By rotating the wheel wrench clockwise, raise the
vehicle until the wheel just clears the surface.
WARNING!
Raising the vehicle higher than necessary can make
the vehicle unstable and cause a collision. It could
slip off the jack and hurt someone near it. Raise the
vehicle only enough to remove the tire.
5. Remove the wheel nuts and pull the wheel off. Install
the spare wheel and wheel nuts with the cone shaped end
of the nuts toward the wheel on single rear wheel (SRW)
models. On dual rear wheel models (DRW) the lug nuts
are a two-piece assembly with a flat face. Lightly tighten
the nuts. To avoid risk of forcing the vehicle off the jack,
do not fully tighten the nuts until the vehicle has been
lowered.6. Using the wheel wrench, finish tightening the nuts
using a crisscross pattern. The correct nut tightness is
135 ft lbs (183 N·m) torque for single rear wheel (SRW)
models and 145 ft lbs (197 N·m) for dual rear wheel
models. If in doubt about the correct tightness, have them
checked with a torque wrench by your authorized dealer
or at a service station.
WARNING!
A loose tire or jack thrown forward in a collision or
hard stop could injure someone in the vehicle. Al-
ways stow the jack parts and the extra tire and wheel
in the places provided.
7. Install wheel center cap (if equipped) and remove
wheel blocks. Do not install chrome or aluminum wheel
center caps on the spare wheel. This may result in cap
damage.
386 WHAT TO DO IN EMERGENCIES