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Tire Inflation Pressure – 4500/5500 With Steel
Carcass Ply Tires
This type of tire utilizes steel cords in the sidewall. As
such, they cannot be treated like normal light truck tires.
Adjusting tire pressure must be performed by personnel
trained, supervised and equipped accordingly. Inflation Pressure Adjustment When Mounted To
Vehicle
During procedures when adding tire inflation pressure,
the technician or individual must utilize a remote infla-
tion device, and ensure that all persons are clear of the
trajectory area.
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These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes 1/16 in (2 mm). When the tread is worn to the
tread wear indicators, the tire should be replaced.
Many states have laws requiring tire replacement at this
point.
Life Of Tire
The service life of a tire is dependent upon varying
factors including, but not limited to:
• Driving style
• Tire pressure
• Distance driven WARNING!Tires and spare tire should be replaced after six years,
regardless of the remaining tread. Failure to follow
this warning can result in sudden tire failure. You
could lose control and have a collision resulting in
serious injury or death.
Keep dismounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease, and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (refer to the paragraph on
“Tread Wear Indicators”). Refer to the “Tire and Loading328 STARTING AND OPERATING
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WARNING! (Continued)• Never use a tire with a smaller load index or
capacity, other than what was originally equipped
on your vehicle. Using a tire with a smaller load
index could result in tire overloading and failure.
You could lose control and have a collision result-
ing in serious injury or death.
• Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control resulting in
serious injury or death.
CAUTION!Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings. SUPPLEMENTAL TIRE PRESSURE INFORMATION
— IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers [150 lbs (68 kg) each] plus 200 lbs (91 kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
TIRE CHAINS
Use “Class U” chains or other traction aids that meet SAE
Type “U” specifications.
NOTE: Chains must be the proper size for the vehicle,
as recommended by the chain manufacturer.
CAUTION!To avoid damage to your vehicle, tires or chains,
observe the following precautions:
(Continued)330 STARTING AND OPERATING
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CAUTION! (Continued)• 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 position
on the vehicle. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires will maintain proper position.
FUEL REQUIREMENTS
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 use of premium gasoline
is not recommended, as it will not provide any benefit
over regular gasoline in these engines.
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 worldwide 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. 5 STARTING AND OPERATING 335
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If a Non-FFV vehicle is inadvertently fueled with E-85
fuel, the engine will have some or all of these symptoms:
• operate in a lean mode
• OBD II “Malfunction Indicator Light” on
• poor engine performance
• poor cold start and cold drivability
• increased risk for fuel system component corrosion
To fix a Non-FFV vehicle inadvertently fueled once with
E-85 perform the following:
• drain the fuel tank (see your authorized dealer)
• change the engine oil and oil filter
• disconnect and reconnect the battery to reset the
engine controller memory More extensive repairs will be required for prolonged
exposure to E-85 fuel.
MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not the 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 those
allowed in the United States. MMT is prohibited in
Federal and California reformulated gasoline.
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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 perfor-
mance, damage the emission control system.
(Continued) CAUTION! (Continued)• 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 authorized 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 per-
sists, lighten the load, or engine piston damage
may result.
(Continued)338 STARTING AND OPERATING
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WARNING! (Continued)• Guard against carbon monoxide with proper
maintenance. Have the exhaust system inspected
every time the vehicle is raised. Have any abnor-
mal 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.
• 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.340 STARTING AND OPERATING
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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 1/4 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
will display in the EVIC telltale display area.
Refer to “Electronic Vehicle Information Center (EVIC) in
“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.
5 STARTING AND OPERATING 341