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ENGINE RUNAWAY
WARNING!
In case of engine runaway due to flammable fumes
from gasoline spills or turbocharger oil leaks being
sucked into the engine do the following to help avoid
personal injury and/or vehicle damage:
1. Shut off engine ignition switch.
2. Using a CO
2or dry chemical type fire extin-
guisher, direct the spray from the fire extinguisher
into the grille on the passenger side so that the spray
enters the engine air intake.
The inlet for the engine air intake is located behind
the passenger side headlamp and receives air
through the grille
FUEL REQUIREMENTS
Fuel Requirements (5.7L Gas Engines)
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 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.
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Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of ªregularº 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 ªReformulated Gasoline.º
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.
CAUTION!
DO NOT use gasolines containing Methanol or E85
Ethanol. Use of these blends may result in starting
and driveability problems and may damage critical
fuel system components.
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Problems that result from using methanol/gasoline or
E85 Ethanol blends are not the responsibility of the
manufacturer. While MTBE is an oxygenate made from
Methanol, it does not have the negative effects of Metha-
nol.
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.
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:
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²The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
damage the emission control system.
²An 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.
²When 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.
²The 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:
²Do 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
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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.
²Guard against carbon monoxide with proper mainte-
nance. 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.
²Keep the liftgate closed when driving your vehicle to
prevent carbon monoxide and other poisonous ex-
haust gases from entering the vehicle.
Fuel Requirements (6.7L Diesel Engines)
Use good quality diesel fuel from a reputable supplier in
your vehicle. Federal law requires that you must fuel this
vehicle with Ultra Low Sulfur Highway Diesel fuel (15
ppm Sulfur maximum) and prohibits the use of Low
Sulfur Highway Diesel fuel (500 ppm Sulfur maximum)to avoid damage to the emissions control system. For
most year-round service, No. 2 diesel fuel meeting ASTM
specification D-975 Grade S15 will provide good perfor-
mance. If the vehicle is exposed to extreme cold (below
20ÉF or -7ÉC), or is required to operate at colder-than-
normal conditions for prolonged periods, use climatized
No. 2 diesel fuel or dilute the No. 2 diesel fuel with 50%
No. 1 diesel fuel. This will provide better protection from
fuel gelling or wax-plugging of the fuel filters.
WARNING!
Do not use alcohol or gasoline as a fuel blending
agent. They can be unstable under certain conditions
and hazardous or explosive when mixed with diesel
fuel.
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Diesel fuel is seldom completely free of water. To prevent
fuel system trouble, drain the accumulated water from
thefuel/water separator using the fuel/water separator
drain provided. If you buy good quality fuel and follow
the cold weather advice above, fuel conditioners should
not be required in your vehicle. If available in your area,
a high cetane ªpremiumº diesel fuel may offer improved
cold-starting and warm-up performance.
Fuel Specifications
The Cummins Turbocharged, Charge Air Cooled, Diesel
engine has been developed to take advantage of the high
energy content and generally lower cost No. 2 Ultra Low
Sulfur diesel fuel or No. 2 Ultra Low Sulfur climatized
diesel fuels. Experience has shown that it also operates
on No. 1 Ultra Low Sulfur diesel fuels or other fuels
within specification.NOTE:A maximum blend of 5% biodiesel meeting
ASTM specification D-6751 may be used with your
Cummins Diesel equipped vehicle.
NOTE:In addition, commercially available fuel addi-
tives are not necessary for the proper operation of your
Cummins Diesel equipped vehicle.
NOTE:No. 1 Ultra Low Sulfur diesel fuel should only
be used where extended arctic conditions (-10ÉF or -23ÉC)
exist.
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ADDING FUEL
Adding Fuel (Gas Engines)
CAUTION!
Damage to the fuel system or emission control sys-
tem 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
after-market cap can cause the MIL (Malfunction
Indicator Light) to illuminate, due to fuel vapors
escaping from the system.
CAUTION!
A poorly fitting gas cap may cause the Malfunction
Indicator Light to turn on.
CAUTION!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
NOTE:When the fuel nozzle ªclicksº or shuts off, the
fuel tank is full.
WARNING!
²Never have any smoking materials lit in or near
the vehicle when the gas cap is removed or the
tank filled.
²Never add fuel to the vehicle when the engine is
running. This is in violation of most state and
federal fire regulations and will cause the Mal-
function Indicator Light to turn on.
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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 vehicles diagnostic system determines that the fuel
filler cap in loose, improperly installed, or damaged, a
GASCAP message will be displayed in the instrument
cluster. Tighten the gas cap until a ªclickingº sound is
heard. This is an indication that the gas cap is properly
tightened. Press the odometer reset button to turn the
message off. If the problem persists, the message will
appear the next time the vehicle is started. This might
indicate a damaged cap. If the problem is detected twice
in a row, the system will turn on the Malfunction
Indicator Light (MIL). Resolving the problem will turn
the MIL light off.
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