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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 and damage the emissions control system.
• 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 ser-
vice. Contact your authorized dealer for service
assistance.
(Continued)
CAUTION! (Continued)
•The use of fuel additives, which are now being
sold as octane enhancers, is not recommended.
Most of these products contain high concentrations
of methanol. Fuel system damage or vehicle perfor-
mance problems resulting from the use of such
fuels or additives is not the responsibility of the
manufacturer.
NOTE: Intentional tampering with the emissions control
system can result in civil penalties being assessed against
you.
384 STARTING AND OPERATING
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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)
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.
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.
6
WHAT TO DO IN EMERGENCIES 423
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Jacking Instructions
Instructions
WARNING!
Carefully follow these tire changing warnings to
help prevent personal injury or damage to your
vehicle:
•Always park on a firm, level surface as far from the
edge of the roadway as possible before raising the
vehicle.
• Turn on the Hazard Warning flasher.
• Block the wheel diagonally opposite the wheel to
be raised.
• Set the parking brake firmly and set an automatic
transmission in PARK; a manual transmission in
REVERSE.
(Continued)
WARNING! (Continued)
•Never start or run the engine with the vehicle on a
jack.
• 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. If
you need to get under a raised vehicle, take it to a
service center where it can be raised on a lift.
• 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.
6
WHAT TO DO IN EMERGENCIES 425
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(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. For the proper lug nut
torque specifications refer to “Wheel and Tire Torque
Specifications” in this section. 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.
8. Lower the jack to its fully closed position. If the jack will not lower by turning the dial (thumbwheel) by
hand, it may be necessary to use the jack drive tube in
order to lower the jack. Stow the replaced tire, jack,
and tools as previously described.
9. Adjust the tire pressure when possible.
Hub Caps/Wheel Covers — If Equipped
The hub caps must be removed before raising the vehicle
off the ground.
428 WHAT TO DO IN EMERGENCIES
Page 440 of 546
5. Insert a screwdriver or similar tool into the access port(ringed circle) on the bottom of the steering column,
and push and hold the override release lever up.
6. Move the shift lever to the NEUTRAL position.
7. The vehicle may then be started in NEUTRAL.TOWING A DISABLED VEHICLE
This section describes procedures for towing a disabled
vehicle using a commercial wrecker service. If the trans-
mission and drivetrain are operable, disabled vehicles
may also be towed as described under “Recreational
Towing” in the “Starting and Operating” section.
Shift Lever Override Access Port
438 WHAT TO DO IN EMERGENCIES
Page 445 of 546
MAINTAINING YOUR VEHICLE
CONTENTS
ENGINE COMPARTMENT — 5.7L ..........445
ENGINE COMPARTMENT — 6.4L ..........446
ONBOARD DIAGNOSTIC SYSTEM (OBD II) . . .447
▫ Loose Fuel Filler Cap Message ............447
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS ......................... .448
REPLACEMENT PARTS ..................449
DEALER SERVICE ..................... .449
MAINTENANCE PROCEDURES ...........450
▫ Engine Oil ......................... .451▫
Engine Oil Filter ..................... .454
▫ Engine Air Cleaner Filter ................454
▫ Maintenance-Free Battery ...............455
▫ Air Conditioner Maintenance .............456
▫ Front Prop Shaft Lubrication — Four-Wheel Drive
Models ............................ .457
▫ Body Lubrication .....................457
▫ Windshield Wiper Blades ...............457
▫ Adding Washer Fluid ..................458
▫ Exhaust System ..................... .459
7
Page 449 of 546

ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. 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 emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light (MIL).” It
will also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your authorized dealer for service as
soon as possible.
CAUTION!
•Prolonged driving with the MIL on could cause
further damage to the emission control system. It
could also affect fuel economy and driveability.
The vehicle must be serviced before any emissions
tests can be performed.
• If the MIL is flashing, while the engine is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines
that the fuel filler cap is loose, improperly
installed, or damaged, a loose gascap indicator
will display in the EVIC telltale display area.
Refer to “Electronic Vehicle Information Center (EVIC) in7
MAINTAINING YOUR VEHICLE 447
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“Understanding Your Instrument Panel” for further in-
formation. Tighten the fuel filler cap properly and press
the SELECT button to turn off the message. If the
problem continues, the message will appear the next time
the vehicle is started.
A loose, improperly installed, or damaged fuel filler cap
may also turn on the Malfunction Indicator Light (MIL).
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 that require an Inspection and Mainte-
nance (I/M), this check verifies the “Malfunction
Indicator Light (MIL)” is functioning and is not
on when the engine is running, and that the OBD II
system is ready for testing. Normally, the OBD II system will be ready. The OBD II
system may
notbe ready if your vehicle was recently
serviced, recently had a dead battery or a battery replace-
ment. If the OBD II system should be determined not
ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition actuated test, which
you can use prior to going to the test station. To check if
your vehicle’s OBD II system is ready, you must do the
following:
1. Cycle the ignition switch to the ON position, but do not crank or start the engine.
NOTE: If you crank or start the engine, you will have to
start this test over.
2. As soon as you cycle the ignition switch to the ON position, you will see the MIL symbol come on as part
of a normal bulb check.
448 MAINTAINING YOUR VEHICLE