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WARNING!
•Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also be certain to leave an automatic
transmission in Park, a manual transmission in
Reverse or first gear. Failure to do so may allow
the vehicle to roll and cause damage or injury.
•Leaving children in a vehicle unattended is dan-
gerous for a number of reasons. A child or others
could be injured. Children should be warned not
to touch the parking brake or the gear selector
lever. Don’t leave the keys in the ignition. A child
could operate power windows, other controls, or
move the vehicle.
•Be sure the parking brake is fully disengaged before
driving, failure to do so can lead to brake problems
due to excessive heating of the rear brakes.
When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
BRAKE SYSTEM
If power assist is lost for any reason (for example,
repeated brake applications with the engine off), the
brakes will still function. However, you will experience a
substantial increase in braking effort to stop the vehicle.
If either the front or rear hydraulic systems lose normal
capability, the remaining system will still function with
some loss of overall braking effectiveness. This will be
evident by increased pedal travel during application,
greater pedal force required to slow or stop, and activa-
tion of the BRAKE warning lamp and the ABS lamp (if
equipped) during brake use.
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Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial ply tires in sets of four (or 6, in case
of trucks with dual rear wheels). Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized tire dealer for radial tire repairs.
Compact Spare Tire — If Equipped
The compact spare is for temporary emergency use with
radial tires. It is engineered to be used on your style
vehicle only. Since this tire has limited tread life, the
original tire should be repaired (or replaced) and rein-
stalled at the first opportunity.
WARNING!
Temporary use spare tires are for emergency use
only. With these tires, do not drive more than 50 mph
(80 km/h). Temporary-use spare tires have limited
tread life. When two or more tread wear indicators
appear in adjacent grooves, the temporary use spare
tire needs to be replaced. Be sure to follow the
warnings which apply to your spare. Failure to do so
could result in spare tire failure and loss of vehicle
control.
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CAUTION!
3500 Dual Rear Tires have only one approved direc-
tion of rotation. This is to accommodate the asym-
metrical design (tread pattern) of the ON/OFF road
tire and the use of Outline White Letter (OWL) tires.
•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 posi-
tion on the truck. For example, if the spare is used
to replace an outer rear tire it will have to be
remounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetri-
cal tires and the white writing of the OWL tires
will maintain proper position.
FUEL REQUIREMENTS
All engines (except 5.7L engines) are de-
signed to meet all emissions regulations
and provide excellent fuel economy and
performance when using high quality un-
leaded “regular” gasoline having an oc-
tane rating of 87. The routine use of pre-
mium gasoline is not recommended.
Under normal conditions the use of premium fuel will
not provide a benefit over high quality regular gasolines
and in some circumstances may result in poorer perfor-
mance.
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 octane
for optimum performance.The routine use
3.7L/4.7L
Engines
5.7L Engines
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of premium gasoline is not recommended. The use of
premium gasoline will provide no benefit over high
quality regular and mid-grade gasolines, and in some
circumstances may result in poorer performance.
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 world-wide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performanceand durability for your vehicle. We recommend the use
of gasolines that meet the WWFC specifications if they
are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline.”
Reformulated gasolines contain oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
We strongly support the use of reformulated gasolines.
Properly blended reformulated gasolines will provide
excellent performance and durability for the engine and
fuel system components.
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WARNING!
•Remove the fuel tank filler tube cap (gas cap)
slowly to prevent fuel spray from the filler neck
which may cause injury.
•The volatility of some gasolines may cause a
buildup of pressure in the fuel tank that may
increase while you drive. This pressure can result
in a spray of gasoline and/or vapors when the cap
is removed from a hot vehicle. Removing the cap
slowly allows the pressure to vent and prevents
fuel spray.
•Never allow any lit smoking materials near the
vehicles while removing the cap or filling the
tank.
•Never add fuel to the vehicle when the engine is
running.
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 performance,
damage the emission 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 service.
Contact your dealer for service assistance.
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•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 persists, lighten the load,
or engine piston damage may result.
•The 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.
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.
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Fuel Requirements
Your vehicle will operate on both unleaded gasoline with
an octane rating of 87, or E-85 fuel, or any mixture of
these two.
For best results, a refueling pattern that alternates be-
tween E-85 and unleaded gasoline should be avoided.
When you do switch fuels, it is recommended that
•you do not switch when the fuel gauge indicates less
than 1/4 full
•you do not add less than 5 gallons when refueling
•you operate the vehicle immediately after refueling for
a period of at least 5 minutes
Observing these precautions will avoid possible hard
starting and/or significant deterioration in drivability
during warm up.NOTE:When the ambient temperature is above 90°F,
you may experience hard starting and rough idle follow-
ing start up even if the above recommendations are
followed.
Selection Of Engine Oil For Flexible Fuel Vehicles
(E-85) and Gasoline Vehicles
Whether operating the vehicle on an E-85 ethanol fuel or
unleaded gasoline the engine oil requirements are the
same. Refer to the “Maintenance Procedures” section of
this manual for the proper quality and viscosity engine
oil. (See page 355 for more information.)
Starting
The characteristics of E-85 fuel make it unsuitable for use
when ambient temperatures fall below 0°F. In the range
of 0°F to 32°F, you may experience an increase in the time
it takes for your engine to start, and a deterioration in
drivability (sags and/or hesitations) until the engine is
fully warmed up.
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NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
CAUTION!
Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
As with any vehicle, do not park or operate this vehicle in
areas where combustible materials such as grass or leaves
can come in contact with a hot exhaust system.A scorching odor may be detected if you continue to run
a malfunctioning engine. The odor may indicate severe
and abnormal catalyst overheating. If this occurs, the
vehicle should be stopped, the engine shut off and the
vehicle allowed to cool. Service, including a tune-up to
manufacturer’s specifications should be obtained imme-
diately.
To minimize the possibility of catalyst damage:
•Do not try to start the engine by pushing or towing the
vehicle.
•Do not idle the engine with any spark plug wires
disconnected or removed.
•Do not idle the engine for prolonged periods during
very rough idle or malfunctioning operating condi-
tions.
•Do not allow vehicle to run out of fuel.
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