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ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Vehicles equipped with California emissions controls
have a sophisticated onboard diagnostic system called
OBDII. This system monitors the performance of the
emissions, engine, and automatic transmission control
systems. When these systems are operating properly,
your vehicle will provide excellent performance and fuel
economy, as well as engine emissions well within current
government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light.” It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be driveable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
Prolonged driving with the “Malfunction Indicator
Light” on could cause further damage to the emission
control system. It could also affect fuel economy and
driveability. The vehicle must be serviced before any
emissions tests can be performed.
If the “Malfunction Indicator Light” is flashing,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
REPLACEMENT PARTS
Use of genuine Moparparts for normal/scheduled
maintenance and repairs is highly recommended to in-
sure the designed performance. Damage or failures
caused by the use of non-Mopar parts for maintenance
and repairs will not be covered by the manufacturer’s
warranty.
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CAUTION!
To maintain your vehicle safely follow these
guidelines:
•Watch your vehicle’s mileage and check yourMainte-
nance Schedulesregularly for required servicing. Ex-
cessive wear or damage to certain vehicle components
can result if required services are not performed.
•If you have your vehicle undercoated, inspect for
undercoating material on the propeller shafts. Such
material could cause the shafts to become unbalanced
and result in drivetrain vibrations. Remove any under-
coating with solvent.
•If you have your vehicle undercoated, make sure no
undercoating material is sprayed on the exhaust sys-
tem or components of the seat belt system.NOTE:It is not possible for the manufacturer and
Cummins, Inc. to anticipate every possible circumstance
that can involve a potential hazard.
WARNING!
To maintain your vehicle safely and avoid personal
injury, follow these guidelines:
•Never spray or pour diesel fuel, flammable liquid or
starting fluids (ether) into the air cleaner assembly, air
intake piping or turbocharger inlet in an attempt to
start the vehicle, unintended engine acceleration may
occur.
•Do not use alcohol or gasoline as a fuel blending agent.
They can be unstable under certain conditions and be
hazardous or explosive when mixed with diesel fuel.
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•If an engine has been operating and the coolant is hot,
allow the engine to cool before you slowly loosen the
filler cap and relieve the pressure from the cooling
system.
•To avoid burns, remember that the engine components
will stay hot after the engine is shut off.
•Do not use gasoline or other flammable materials to
clean parts. Always use approved cleaning solvents.
•Relieve all pressure in the fuel, oil and cooling systems
before any lines, fittings or related items are removed
or disconnected. Be alert for possible pressure when
disconnecting any device from a system that utilizes
pressure. Do not check for pressure leaks with your
hand. High pressure oil or fuel can cause personal
injury.
WARNING!
Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
•Important:All maintenance other than that listed in
this manual, as well as some procedures listed here,
MUSTbe performed by your local Dodge Truck
Dealer. Your authorized Dodge Dealer has been
trained and has the necessary parts to maintain your
engine.
MAINTAINING YOUR VEHICLE 413
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same requirements as stated previously. Your engine oil
filler cap also shows the recommended engine oil viscos-
ity for your vehicle.
Synthetic Engine Oils
You may use synthetic engine oils provided the recom-
mended oil quality requirements are met, and the recom-
mended maintenance intervals for oil and filter changes
are followed.
Materials Added to Engine Oil
The manufacture strongly recommends against the addi-
tion of any additives (other than leak detection dyes or
lube odorants) to the engine oil. Engine oil is an engi-
neered product and it’s performance may be impaired by
supplemental additives.
NOTE:The manufacturer offers a lube odorant (Mopar
Diesel Fresh) for diesel engines crankcases. The lube
odorant is recommended by the manufacturer to reduce
the sulfur smell that may occur during engine idling.
Engine Oil Filter
Refer to Fluids, Lubricants and Genuine Parts for the
correct part number. The engine oil filter should be
changed ateveryengine oil change.
Engine Oil And Filter — Change
Operate the engine until the coolant temperature reaches
140°F (60°C). Shut the engine off. Remove the oil drain
plug.
Use a container that can hold at least 12 quarts (11.3
Liters) to hold the used oil.
Always check the condition of the used oil. This can give
you an indication of some engine problems that might
exist.
•Thin, black oil indicates fuel dilution.
•Milky discoloration indicates coolant dilution.
MAINTAINING YOUR VEHICLE 419
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CAUTION!
When using an engine cleaner or a degreaser, be sure
to wrap and tape the Filter Minder™ to protect the
plastic housing from damage and discoloration.
CAUTION!
Many aftermarket performance air filter elements do
not adequately filter the air entering the engine. Use
of such filters can severely damage your engine.
Draining Fuel/Water Separator Filter (5.9L Diesel
Engine)
CAUTION!
Do not drain the fuel/water separator filter when the
engine is running.
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NOTE:Care should be taken in disposing of used fluids
from your vehicle. Used fluids, indiscriminately dis-
carded, can present a problem to the environment. Con-
tact your local authorized dealer, service station, or
government agency for advice on recycling programs
and for where used fluids and filters can be properly
disposed of in your area.
NOTE:The fuel filter and water separator assembly is
located on the driver’s side of the engine.
Drain a small amount from the fuel/water separator
filter periodically or when the WATER IN FUEL indicator
lamp is on. Pull outward on the drain valve lever, located
on the side of the filter, and allow any accumulated water
to drain. Hold the drain valve open until all water and
contaminants have been removed. Close the drain release
valve, by returning it to the inward position, when clean
fuel is visible.NOTE:The Fuel / Water separator drain valve is
identified by its yellow handle and is located on the
inboard side of the fuel filter housing.
If more than a couple ounces of fuel has been drained,
follow the directions below for “Priming if the engine has
run out of fuel.”
WARNING!
Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
Priming if the engine has run out of fuel
1. Add a substantial quantity of fuel to the tank 5 to 10
gallons (19L to 38L).
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2. Crank the engine for 1 to 2 seconds. If the engine does
not start, then release the key or starter button back to the
RUN position (do not turn the key back to the OFF
position). The electric fuel transfer pump will continue to
run and purge air from the system for about 25 seconds.
After 25 seconds, attempt to start the engine again.
3. Start the engine using the Normal Starting Procedure.
4. Repeat the procedure if the engine does not start.
CAUTION!
Do not engage the starter motor for more than 15
seconds at a time. Allow two minutes between the
cranking intervals.
NOTE:The engine may run rough until the air is forced
from all the fuel lines.
CAUTION!
Diesel fuel will damage black top paving surfaces.
Drain the filter into an appropriate container.
WARNING!
Do not use alcohol or gasoline as a fuel blending
agent. They can be unstable under certain conditions
and be hazardous or explosive when mixed with
diesel fuel.
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CAUTION!
Due to lack of lubricants in alcohol or gasoline, the
use of these fuels can cause damage to the fuel
system.
NOTE:A maximum blend of 5% biodiesel, meeting
ASTM specification D-6751 may be used with your
Cummins Diesel equipped vehicle.
NOTE:As sufficient testing as not been completed,
ethanol blends are not recommended or approved for use
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.
Draining Fuel/Water Separator Filter (6.7L Diesel
Engine)
CAUTION!
Do not drain the fuel/water separator filter when the
engine is running.
430 MAINTAINING YOUR VEHICLE