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WARNING!
•Never have any smoking materials lit in or near the
vehicle when the fuel filler cap is removed or the
tank filled.
•Never add fuel to the vehicle when the engine is
running.
Avoid Using Contaminated Fuel
Fuel that is contaminated by water or dirt can cause
severe damage to the engine fuel system. Proper main-
tenance of the engine fuel filter and fuel tank is essential.
Refer to “Maintenance Procedures” in “Maintaining Your
Vehicle” for further information.
Bulk Fuel Storage — Diesel Fuel
If you store quantities of fuel, good maintenance of the
stored fuel is also essential. Fuel contaminated with
water will promote the growth of “microbes.” Thesemicrobes form “slime” that will clog the fuel filtration
system and lines. Drain condensation from the supply
tank and change the line filter on a regular basis.
NOTE:When a diesel engine is allowed to run out of
fuel, air is pulled into the fuel system.
If the vehicle will not start, refer to “Maintenance
Procedures/Priming If The Engine Has Run Out Of Fuel”
in “Maintaining Your Vehicle” for further information.
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.
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Diesel Exhaust Fluid Storage
Diesel Exhaust Fluid (DEF) is considered a very stable
product with a long shelf life. If DEF is kept in tempera-
tures between 10° and 90°F (-12° and 32°C), it will last a
minimum of one year.
DEF is subject to freezing at the lowest temperatures. For
example, DEF may freeze at temperatures at or below 12°
F (-11° C). The system has been designed to operate in
this environment.
NOTE:When working with DEF, it is important to know
that:
•Any containers or parts that come into contact with
DEF must be DEF compatible (plastic or stainless
steel). Copper, brass, aluminum, iron or non-stainless
steel should be avoided as they are subject to corrosion
by DEF.
•If DEF is spilled, it should be wiped up completely.
Adding Diesel Exhaust Fluid
The DEF gauge (located on the instrument cluster) will
display the level of DEF remaining in the tank. Refer to
“Instrument Cluster” and “Instrument Cluster Descrip-
tions” in “Understanding Your Instrument Panel” for
further information.
NOTE:Driving conditions (altitude, vehicle speed, load,
etc.) will effect the amount of DEF that is used in your
vehicle.
DEF Fill Procedure
NOTE:Refer to “Fluids, Lubricants, and Genuine Parts”
in “Maintaining Your Vehicle” for the correct fluid type.
1. Remove cap from DEF tank (located on drivers side of
the vehicle or in fuel door).
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1 — Diesel Exhaust Fluid Fill Location
2 — Diesel Fuel Fill Location
2. Insert DEF fill adapter/nozzle into DEF tank filler
neck.
DEF Filler Cap Chassis Cab ModelsDEF Filler Cap And Fuel Fill 1500/2500/3500 Models
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CAUTION!
•To avoid DEF spillage, and possible damage to the
DEF tank from overfilling, do not “top off” the DEF
tank after filling.
(Continued)
CAUTION!(Continued)
•DO NOT OVERFILL. DEF will freeze below 12ºF
(-11ºC). The DEF system is designed to work in
temperatures below the DEF freezing point, how-
ever, if the tank is overfilled and freezes, the
system could be damaged.
•When DEF is spilled, clean the area immediately
with water and use an absorbent material to soak
up the spills on the ground.
•Do not attempt to start your engine if DEF is
accidentally added to the diesel fuel tank as it can
result in severe damage to your engine, including
but not limited to failure of the fuel pump and
injectors.
Filling The DEF Tank
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Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, activate TOW/HAUL mode when driving in hilly
areas, or select a lower gear range (using the Electronic
Range Select (ERS) shift control) on more severe grades.
Electronic Speed Control — If Equipped
•Do not use in hilly terrain or with heavy loads.
•When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
•Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, shift the trans-
mission into NEUTRAL and increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
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•Electronically-heated DEF lines
•DEF control module
•NOx sensors
•NH3 sensor
•Temperature sensors
•SCR catalyst
The DEF injection system and SCR catalyst enable the
achievement of diesel emissions requirements; while
maintaining outstanding fuel economy, drivability,
torque and power ratings.
Refer to “Electronic Vehicle Information Center (EVIC)”
in “Understanding Your Instrument Panel” for system
messages and warnings.NOTE:
•Your vehicle is equipped with a DEF injection system.
You may occasionally hear an audible clicking noise.
This is normal operation.
•The DEF pump will run for a period of time after
engine shutdown to purge the DEF system. This is
normal operation.
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MAINTAINING YOUR VEHICLE
CONTENTS
ENGINE COMPARTMENT — 6.7L DIESEL —
SIX-SPEED 68RFE (2500/3500 Models).......289
ENGINE COMPARTMENT — 6.7L DIESEL —
SIX-SPEED AS69RC HD (3500/CHASSIS CAB
MODELS)............................290
MAINTENANCE PROCEDURES...........291
▫Engine Oil..........................292
▫Engine Air Cleaner Filter................296
▫Draining Fuel/Water Separator Filter.......300
▫Engine Mounted Fuel Filter Replacement.....302
▫Underbody Mounted Fuel Filter Replacement. .304▫Priming If The Engine Has Run Out Of Fuel . .306
▫Intervention Regeneration Strategy — EVIC
Message Process Flow..................307
▫Diesel Exhaust Fluid...................308
▫Maintenance-Free Batteries..............309
▫Cooling System......................310
▫Charge Air Cooler — Inter-Cooler.........315
▫Brake System........................316
▫Clutch Hydraulic System................317
▫Transfer Case — If Equipped.............317
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Engine Air Cleaner Filter Installation
NOTE:Inspect and clean the housing if dirt or debris is
present before replacing the air filter element.
1. Install the air cleaner filter element into the housing
assembly with the air cleaner filter inspection surface
facing downward.
2. Install the air cleaner cover onto the housing assembly
locating tabs.
3. Install screws to secure the air cleaner cover to the
housing assembly.
Draining Fuel/Water Separator Filter
There are two fuel filter assemblies. One is located on the
driver’s side of the engine. The best access to this water
drain valve is from under the hood. The second one is on
the under body, located in front of the rear axle above the
drive shaft on pick-up models. The Chassis Cab modelssecond filter location is on the frame behind the front
axle. The best access to this water drain valve is from
under the vehicle.
CAUTION!
•Do not drain the fuel/water separator filters when
the engine is running.
•Diesel fuel will damage blacktop paving surfaces.
Drain the filters into an appropriate container.
If water is detected in the water separator while the
engine is running, or while the ignition switch is in the
ON position, the “Water In Fuel Indicator Light” will
illuminate and an audible chime will be heard five times.
At this point you should stop the engine and drain the
water from both of the filters.
300 MAINTAINING YOUR VEHICLE