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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.
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Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
•Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas, which can
kill. Never run the engine in a closed area, such as
a garage, and never sit in a parked vehicle with the
engine running for an extended period. If the
vehicle is stopped in an open area with the engine
running for more than a short period, adjust the
ventilation system to force fresh, outside air into
the vehicle.
(Continued)
WARNING! (Continued)
•Guard against carbon monoxide with proper main-
tenance. Have the exhaust system inspected every
time the vehicle is raised. Have any abnormal
conditions repaired promptly. Until repaired, drive
with all side windows fully open.
ADDING FUEL
CAUTION!
• Damage to the fuel system or emissions control
system could result from using an improper fuel
tank filler tube cap (gas cap). A poorly fitting cap
could let impurities into the fuel system. Also, a
poorly-fitted aftermarket cap can cause the MIL
(Malfunction Indicator Light) to illuminate due to
fuel vapors escaping from the system.
(Continued)
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CAUTION!(Continued)
•A poorly fitting gas cap may cause the MIL to turn
on.
• To avoid fuel spillage and overfilling, do not “top
off” the fuel tank after filling.
NOTE: When the fuel nozzle “clicks” or shuts off the
fuel tank is full.
WARNING!
• Never have any smoking materials lit in or near the
vehicle when the gas cap is removed or the tank is
being filled.
• Never add fuel to the vehicle when the engine is
running. This is in violation of most state and
federal fire regulations and may cause the MIL to
turn on. NOTE:
Tighten the gas cap ¼ turn until you hear one
click. This is an indication that the cap is properly
tightened.
If the gas cap is not tightened properly, the Malfunction
Indicator Light will come on. Be sure the gas cap is
tightened every time the vehicle is refueled.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle. You
could be burned. Always place gas containers on the
ground while filling.
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
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will display in the EVIC telltale display area. Refer to
“Electronic Vehicle Information Center (EVIC) in “Under-
standing Your Instrument Panel” for further information.
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.
VEHICLE LOADING
Certification Label
As required by National Highway Traffic Safety Admin-
istration regulations, your vehicle has a certification label
affixed to the driver’s side door or pillar.
This label contains the month and year of manufacture,
Gross Vehicle Weight Rating (GVWR), Gross Axle Weight
Rating (GAWR) front and rear, and Vehicle Identification
Number (VIN). A Month-Day-Hour (MDH) number isincluded on this label and indicates the Month, Day and
Hour of manufacture. The bar code that appears on the
bottom of the label is your VIN.
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options and cargo.
The label also specifies maximum capacities of front and
rear axle systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the
driver, all passengers, options and cargo.
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.
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Each axle 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 vehi-
cle’s GVWR.
Tire Size
The tire size on the Vehicle Certification 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.
The entire vehicle should first be weighed on a commer-
cial scale to insure that the GVWR has not been exceeded.
The weight on the front and rear of the vehicle should
then be determined separately to be sure that the load is
properly distributed over the front and rear axle. Weigh-
ing the vehicle may show that the GAWR of either the
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NOTE:Check the automatic transmission fluid level
before towing.
Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, turn the “TOW/HAUL” feature ON when driving in
hilly areas, or select a lower gear range (using the
Electronic Range Select (ERS) switches) on more severe
grades.
Electronic Speed Control — If Equipped
• Do not use in hilly terrain or with heavy loads.
• When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
• Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, shift the trans-
mission into NEUTRAL and increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
SNOWPLOW
Snowplow Prep Packages are available as a factory
installed option. These packages include components
necessary to equip your vehicle with a snowplow.
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3. If using another vehicle to jump-start the battery, parkthe vehicle within the jumper cables reach, set the
parking brake and make sure the ignition is OFF.
WARNING!
Do not allow vehicles to touch each other as this
could establish a ground connection and personal
injury could result.
Jump-Starting Procedure
WARNING!
Failure to follow this jump-starting procedure could
result in personal injury or property damage due to
battery explosion.
CAUTION!
Failure to follow these procedures could result in
damage to the charging system of the booster vehicle
or the discharged vehicle.
Connecting The Jumper Cables
1. Connect the positive (+)end of the jumper cable to the
positive (+)post of the discharged vehicle.
2. Connect the opposite end of the positive (+)jumper
cable to the positive (+)post of the booster battery.
3. Connect the negative (-)end of the jumper cable to the
negative (-)post of the booster battery.
4. Connect the opposite end of the negative (-)jumper
cable to a good engine ground (exposed metal part of
the discharged vehicle’s engine) away from the battery
and the fuel injection system.
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WHAT TO DO IN EMERGENCIES 433
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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
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