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Drain the fuel/water separator filters when the “Water In
Fuel Indicator Light” is ON. Within 10 minutes of vehicle
shutdown, turn the engine mounted filter drain valve
(located on the side of the filter assembly) counterclock-
wise 1/4 turn, and turn the under body mounted filter
drain valve (located on the bottom of the filter assembly)
counterclock wise 1 full turn. Then turn the ignition switch
to the ON position, and allow any accumulated water to
drain. Leave the drain valve open until all water and
contaminants have been removed. When clean fuel is
visible, close the drain valves by turning them fully clock-
wise, and turn the ignition switch to OFF.
If more than a couple ounces/milliliters of fuel have been
drained, follow the directions for “Priming If The Engine
Has Run Out Of Fuel.”
Engine Mounted Fuel Filter Replacement
NOTE:
•Using a fuel filter that does not meet the manufacturer’s
filtration and water separating requirements can se-
verely impact fuel system life and reliability.
•
The engine mounted filter housing is equipped with a
No-Filter-No-Run (NFNR) feature. Engine will not run if:
1. No filter is installed.
2. Inferior/Non-approved filter is used. Use of OEM filter is required to ensure vehicle will run.
Engine Mounted Fuel Filter Assembly
1 — Drain Valve
7
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•A maximum blend of 20% biodiesel, meeting ASTM
specification D-7467 may be used with your Cummins
diesel engine. (Pickup models and Chassis Cab models
configured with B20 capability.)
• Use of biodiesel mixture in excess of 20% can negatively
impact the fuel filter’s ability to separate water from the
fuel, resulting in high pressure fuel system corrosion or
damage.
• Ethanol blends are not recommended or approved for
use with your Cummins diesel engine.
• In addition, commercially available fuel additives are
not necessary for the proper operation of your Cummins
diesel engine.
Intervention Regeneration Strategy — Message
Process Flow
The Cummins diesel engine meets all EPA Heavy Duty
Diesel Engine Emissions Standards, resulting in one of the
lowest emitting diesel engines ever produced.
To achieve these emissions standards, your vehicle is
equipped with a state-of-the-art engine and exhaust sys-
tem. The engine and exhaust after-treatment system work
together to achieve the EPA Heavy Duty Diesel Engine Emissions Standards. These systems are seamlessly inte-
grated into your vehicle and managed by the Cummins
Powertrain Control Module (PCM). The PCM manages
engine combustion to allow the exhaust system’s catalyst
to trap and burn Particulate Matter (PM) pollutants, with
no input or interaction on your part.
If the engine is allowed to idle or the truck is driven on low
engine speed drive cycles for more than 2 hours, the
system will automatically enter an emissions operating
mode that will increase the engine idle speed to 900 RPM
(1050 RPM for Chassis Cab). While in this mode, which is
designed to help maintain the diesel particulate filter, the
engine idle speed will return to normal when the brake
pedal is applied. A small change in engine tone or a slight
change in engine performance while accelerating may also
be noticeable at speeds below 20 mph (32 kmh). This
operating mode may last for up to an hour of idle time, or
around 20 minutes of driving time.
Additionally, your vehicle has the ability to alert you to
additional maintenance required on your truck or engine.
Refer to “Instrument Cluster Display” in “Understanding
Your Instrument Panel” for further information.
7
MAINTAINING YOUR VEHICLE 189
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MS.90032) and distilled water for proper corrosion pro-
tection of your engine which contains aluminum com-
ponents.
• Make sure that the coolant expansion bottle overflow
hoses are not kinked or obstructed.
• Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
• Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install ONLY
the correct type thermostat. Other designs may result in
unsatisfactory engine coolant (antifreeze) performance,
poor gas mileage, and increased emissions.
Charge Air Cooler — Inter-Cooler
The charge air cooler is positioned below the radiator and
the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger, where it is pressurized. This pressurized air rap-
idly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through another
hose to the intake manifold of the engine. The air entering the engine has been cooled by about 50° to 100°F (10° to
38°C). This cooling process enables more efficient burning
of fuel resulting in fewer emissions.
To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and radiator
clean and free of debris. Periodically check the hoses
leading to and from the charge air cooler for cracks or loose
clamps resulting in loss of pressure and reduced engine
performance.
Brake System
Brake Master Cylinder — Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immediately
if the “Brake System Warning Light” indicates system
failure.
The brake master cylinder has a translucent plastic reser-
voir. On the outboard side of the reservoir, there is a
“MAX” mark and a “MIN” mark. The fluid level must be
kept within these two marks. Do not add fluid above the
full mark because leakage may occur at the cap.7
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7. Remove the dipstick again and note the fluid level onboth sides. The fluid level reading is only valid if there
is a solid coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be full of fluid if
the actual level is at or above the hole. The fluid level
should be between the “HOT” (upper) reference holes
on the dipstick at normal operating temperature. If the
fluid level is low, add fluid through the dipstick tube to
bring it to the proper level. Do not overfill.Use ONLY
the specified fluid (see Fluids, Lubricants, and Genuine
Parts for fluid specifications). After adding any quan-
tity of oil through the dipstick tube, wait a minimum of
two minutes for the oil to fully drain into the transmis-
sion before rechecking the fluid level.
NOTE: If it is necessary to check the transmission below
the operating temperature, the fluid level should be be-
tween the two “COLD” (lower) holes on the dipstick with
the fluid at 60-70°F / 16-21°C for 68RFE transmission, or
68-86°F / 20-30°C for AS69RC transmission. Only use the
COLD region of the dipstick as a rough reference when
setting the fluid level after a transmission service or fluid
change. Re-check the fluid level, and adjust as required,
once the transmission reaches normal operating tempera-
ture.CAUTION!
If the fluid temperature is below 50°F (10°C) it may not
register on the dipstick. Do not add fluid until the
temperature is elevated enough to produce an accurate
reading. Run the engine at idle, in PARK, to warm the
fluid.
8. Reinsert the dipstick. Check for leaks. Release the park- ing brake.
NOTE: To prevent dirt and water from entering the
transmission after checking or replenishing fluid, make
sure that the dipstick cap is properly reseated. It is normal
for the dipstick cap to spring back slightly from its fully
seated position, as long as its seal remains engaged in the
dipstick tube.
Fluid And Filter Changes
Refer to the “Maintenance Schedule” for the proper main-
tenance intervals.
In addition, change the fluid and filter(s) if the fluid
becomes contaminated (with water, etc.), or if the transmis-
sion is disassembled for any reason.
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