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Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle's
performance:
²The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
damage the emission control system.
²An 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 dealer for service assistance.
²When 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 persists, lighten the load,
or engine piston damage may result.
²The use of fuel additives which are now being sold as
octane enhancers is not recommended. Many of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
338 STARTING AND OPERATING
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An EXAMPLE of a loaded vehicle is shown in the
following chart. Note that neither GVWR nor GAWR
capabilities are exceeded. Overloading can cause poten-
tial safety hazards and shorten service life.
NOTE: The weights shown in this chart are not
necessarily the weights for your vehicle. Also, the
amount of load added to both the front and rear axles
can be computed after the vehicle has been weighed
both in its(curb weight(condition, and in its(loaded
and ready for operation(condition.Gross Vehicle Weight Rating (GVWR) 6500 LBS.
344 STARTING AND OPERATING
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JACKING AND TIRE CHANGING
WARNING!
²Being 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.
²The 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.
All Models
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.
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NOTE:The winch mechanism is designed for use with
the jack extension tube only. Use of an air wrench or other
power tools is not recommended and can damage the
winch.
Tire Changing Procedure
WARNING!
Getting under a jacked-up vehicle is dangerous. The
vehicle could slip off the jack and fall on you. You
could be crushed. Never get 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.
Do not raise this vehicle using a bumper jack. The jack is
designed as a tool for changing tires on this vehicle only.It is not recommended that the jack be used for service
purposes or to lift more than one wheel at a time.
Preparations
Park the vehicle on a firm level surface, avoiding ice or
slippery areas. Set the parking brake and place the gear
selector in PARK (automatic transmission) or REVERSE
(manual transmission). On four-wheel drive vehicles,
shift the transfer case to the ª4Lº position.
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.
²Turn on the Hazard Warning Flasher.
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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 an accident. 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 the rear wheel models.
6. Using the wheel wrench, finish tightening the nuts
using a crisscross pattern. Correct nut tightness is 135 ft.
lbs. (183 N´m) torque.If in doubt about the correct tight-
ness, have them checked with a torque wrench by your
dealer or at a service station.
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MAINTAINING YOUR VEHICLE
CONTENTS
mEngine CompartmentÐ 5.7L...............384
mOnboard Diagnostic System (OBD II).........385
NLoose Fuel Filler Cap Message............385
mEmissions Inspection And Maintenance
Programs............................386
mReplacement Parts......................387
mDealer Service.........................388
mMaintenance Procedures..................388
NEngine Oil..........................389NEngine Oil Filter......................392
NDrive Belts Ð Check Condition And Tension . . 393
NSpark Plugs.........................393
NSpark Plug Wires Ð If Equipped..........393
NEngine Air Cleaner Filter................393
NEngine Fuel Filter.....................394
NCatalytic Converter....................394
NEmission-Related Components............396
NMaintenance Free Battery................396
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ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Vehicles equipped with California emissions controls
have a sophisticated onboard diagnostic system called
OBDII. This system monitors the performance of the
emissions, engine, and automatic transmission control
systems. When these systems are operating properly,
your vehicle will provide excellent performance and fuel
economy, as well as engine emissions well within current
government regulations.
If any of these systems require service, the OBD II system
will turn on the ªMalfunction Indicator Light.º It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be driveable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
Prolonged driving with the ªMalfunction Indicator
Lightº on could cause further damage to the emis-
sion control system. It could also affect fuel economy
and driveability. The vehicle must be serviced before
any emissions tests can be performed.
If the ªMalfunction Indicator Lightº is flashing,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Loose Fuel Filler Cap Message
If the vehicles diagnostic system determines that the fuel
filler cap in loose, improperly installed, or damaged, a
GASCAP message will be displayed in the instrument
cluster. Tighten the gas cap until a ªclickingº sound is
heard. This is an indication that the gas cap is properly
tightened. Press the odometer reset button to turn the
MAINTAINING YOUR VEHICLE 385
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message off. If the problem persists, the message will
appear the next time the vehicle is started. This might
indicate a damaged cap. If the problem is detected twice
in a row, the system will turn on the Malfunction
Indicator Light (MIL). Resolving the problem will turn
the MIL light off.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle's emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition key actuated test
which you can use prior to going to the test station. To
check if your vehicle's OBD system is ready, you must do
the following:
1. Insert your ignition key into the ignition switch.
2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
386 MAINTAINING YOUR VEHICLE