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Follow the recommended tire rotation frequency for your
type of driving found in the “Maintenance Schedules”
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.
FUEL REQUIREMENTS
The 3.7L/4.7L engines are designed to
meet all emissions regulations and provide
excellent fuel economy and performance
when using high quality unleaded “regu-
lar” gasoline having an octane rating of 87.
The routine use of premium gasoline is not
recommended. Under normal conditions the use of pre-
mium fuel will not provide a benefit over high quality
regular gasoline and in some circumstances may result in
poorer performance.
The 4.7 HO 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 91. The manu-
facturer recommends the use of 91 octane
for optimum performance.
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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, performance
and 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.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE and ETBE. Oxygen-
ates are required in some areas of the country during the
winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.
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CAUTION!
DO NOT use gasoline containing Methanol or E85
Ethanol. Use of these blends may result in starting
and driveability problems and may damage critical
fuel system components.
NOTE: 4.7L Engine — If Equipped, is now rated for
E85 Ethanol use. Only vehicles with the E-85 fuel filler
door label can operate on E-85. For more information,
refer to “Flexible Fuel” in this section.
Problems that result from using methanol/gasoline
blends are not the responsibility of the manufacturer.
While MTBE is an oxygenate made from Methanol, it
does not have the negative effects of Methanol.
MMT In Gasoline
MMT is a manganese-containing metallic additive that is
blended into some gasoline to increase octane. Gasolines
blended with MMT provide no performance advantage
beyond gasolines of the same octane number without
MMT. Gasolines blended with MMT reduce spark plug
life and reduce emission system performance. We recom-
mend that gasolines free of MMT be used in your vehicle.
The MMT content of gasoline may not be indicated on
the gasoline pump; therefore, you should ask your gaso-
line retailer whether or not his/her gasoline contains
MMT.
It is even more important to look for gasolines without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited in Federal and California reformulated gasolines.
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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 performance,
damage the emission control system.
•An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter tooverheat. 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.
•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.
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ADDING FUEL
NOTE:If fuel is poured from a portable container, the
container should have a flexible nozzle long enough to
extend into the fuel filler tube.
CAUTION!
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.
NOTE:Tighten the gas cap until you hear a “clicking”
sound. This is an indication that the gas cap is properly
tightened. Make sure that the gas cap is tightened each
time the vehicle is refueled.
Fuel Cap Holder
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WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle or on a
truck bed. You could be burned. Always place gas
containers on the ground while filling.
Fuel Filler Cap (Gas Cap)
The gas cap is behind the fuel filler door. If the gas cap is
lost or damaged, be sure the replacement cap is for use
with this vehicle.
CAUTION!
Damage to the fuel system or emission 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.
WARNING!
•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.
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FLEXIBLE FUEL— IF EQUIPPED
E-85 General Information
The information in this section is for Flexible Fuel ve-
hicles only. These vehicles can be identified by the unique
fuel filler door label that statesEthanol (E-85) or Un-
leaded Gasoline Only.This section only covers those
subjects that are unique to these vehicles. Please refer to
the other sections of this manual for information on
features that are common between Flexible Fuel and
gasoline only powered vehicles.
CAUTION!
Only vehicles with the E-85 fuel filler door label can
operate on E-85.
ETHANOL FUEL (E-85)
E-85 is a mixture of approximately 85% fuel ethanol and
15% unleaded gasoline.
WARNING!
Ethanol vapors are extremely flammable and could
cause serious personal injury. Never have any smok-
ing materials lit in or near the vehicle when remov-
ing the fuel filler tube cap (gas cap) or filling the
tank. Do not use E-85 as a cleaning agent and never
use it near an open flame.
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.
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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.
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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