
Replace the fuel filter with Motorcraft Part No. F81Z-9N184–AA
(FD-4596).
1. Stop the vehicle andshut offthe engine.
The vehicle must be stopped with the engine off when draining
the HFCM. Fuel may ignite if separator is drained while the
engine is running or vehicle is moving.
2. Locate the module and place an
appropriate container under the
drain plug (see illustration).
3. Remove the drain plug by turning it counterclockwise. Allow to drain
for approximately 25 seconds or until clean fuel is observed. Install the
drain plug by turning it clockwise until it is firmly seated.
4. Verify that the drain plug is closed and sealed, then remove the
container from under the vehicle.
5. Restart the engine and check WATER IN FUEL indicator light; it
should be illuminated. If it continues to illuminate, have the fuel system
checked and repaired.
Draining the fuel filter/water separator - Cummins B engine
Refer to your engine operator’s manual for service procedures.
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Fuel filter replacement - Caterpillar engine
The fuel filter/water separator is
located on the left side of the
engine. Replace the fuel filter/water
separator as recommended in the
general maintenance information
section, or sooner if it becomes
plugged. Vehicles operated on fuel
with more than average impurities
may require replacement of the fuel
filter more frequently. The spin-on
filter has a water drain valve built
into the bottom of the filter canister.
Removal
1. Using an oil filter wrench, remove the filter.
2. Carefully clean the mating surfaces.
Installation
1. Fill the filter with clean, fresh diesel fuel.
2. Coat the filter seal with clean, fresh diesel fuel.
3. Hand-tighten the filter until it seats firmly against the mount, then
tighten (by hand) an additional
1⁄3to1⁄2turn.
4. Start the engine and check for fuel leaks.
Fuel filter replacement - 6.0L Power Stroke engine
Your vehicle is equipped with two fuel filters; one mounted on top of the
engine and the other is mounted inside the frame rail under the
driver-side floorboard near the transmission. Both filters should be
replaced at the same time.
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Removal - Engine-mounted fuel filter
1. Remove the fuel filter cap by
turning counterclockwise.
2. Remove and discard the old fuel
filter element.
3. Carefully clean the mating
surfaces.
Removal - in-line fuel filter
1. Remove the fuel filter cap by
turning counterclockwise.
2. Remove and discard the old fuel
filter element.
3. Carefully clean the mating
surfaces.
Installation-both
The engine will not run properly if the fuel filter is not installed
in housing.
1. Install new fuel filter into the fuel filter housing.
2. Tighten cap onto fuel filter housing slowly, allowing fuel to soak into
the fuel filter element. Tighten cap until it contacts the housing.
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After replacing the fuel filter, the engine will purge the trapped
air as it runs. The engine may run roughly and smoke until the air
is completely eliminated.
Using a fuel which has more than average impurities may require
the fuel filter to be replaced more frequently than the service
interval specifies.
Fuel filter replacement - Cummins B engine
Refer to your engine operator’s manual for service intervals and procedures.
FUEL CONSUMPTION IMPROVEMENT MEASURES
There are two important factors you can control to improve fuel
economy: the mechanical condition of your vehicle and how you drive it.
A properly maintained vehicle will deliver better performance than a
neglected vehicle. Always follow your maintenance schedule to keep your
vehicle in top operating condition.
Also, your driving habits have a significant influence on use of fuel. By
following these suggestions, you can stretch your fuel use:
•Avoid changes in speed as much as possible.
•Anticipate changing traffic conditions. Sudden stops and fast
acceleration waste fuel.
•Avoid extensive idling.
•Do not drive with your foot resting on the brake pedal.
Essentials of good fuel economy
Measuring techniques
Your best source of information about actual fuel economy is you, the
driver. You must gather information as accurately and consistently as
possible. Fuel expense, frequency of fill-ups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economy measurements during the first 1,600 km (1,000
miles) of driving (engine break-in period). You will get a more accurate
measurement after 3,000 km–5,000 km (2,000 miles-3,000 miles).
The advertised fuel capacity of the fuel tank(s) on your vehicle is equal
to the rated refill capacity of the fuel tank(s) as listed inFuel tanksin
this chapter. The advertised capacity is the amount of the Indicated
Capacity and the Empty Reserve combined. Indicated Capacity is the
difference in the amount of fuel in a full tank and a tank when the fuel
gauge indicates empty. Empty Reserve is the small amount of usable fuel
remaining in the fuel tank after the fuel gauge indicates empty.
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The amount of Empty Reserve varies and should not be relied
upon to increase driving range. When refueling your vehicle after
the fuel gauge indicates empty, you might not be able to refuel
the full amount of the advertised capacity of the fuel tank due to
the empty reserve still present in the tank.
Filling the tank
For consistent results:
•Use the same fill rate setting (low—medium—high) each time
during filling.
•Allow three automatic click-offs when filling.
•Always use fuel of a known quality, preferably a national brand.
•Have the vehicle loading and distribution the same every time.
•When refueling a vehicle equipped with dual fuel tanks, if the two
tanks are not filled equally, the fuel gauge reading may fluctuate
slightly until the fuel level between the two tanks balance out and
become equal.
Your results will be most accurate if your filling method is consistent.
Note:For vehicles equipped with dual fuel tanks, engine performance
may degrade if fuel is not added to both tanks when refueling.
Calculating fuel economy
1. Fill the fuel tank(s) completely and record the initial odometer
reading (in kilometers or miles).
2. Each time you fill the tank(s), record the amount of fuel added (in
liters or gallons).
3. After at least three to five tank fill-ups, fill the fuel tank(s) and record
the current odometer reading.
4. Subtract your initial odometer reading from the current odometer
reading.
5. Follow one of the simple calculations in order to determine fuel economy:
•Multiply liters used by 100, then divide by total kilometers traveled.
•Divide total miles traveled by total gallons used.
Keep a record for at least one month and record the type of driving (city
or highway). This will provide an accurate estimate of the vehicle’s fuel
economy under current driving conditions. Additionally, keeping records
during summer and winter will show how temperature impacts fuel
economy. In general, lower temperatures give lower fuel economy.
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Cooling System
•Check the fan for damage to blades; replace, if damaged, with the
recommended parts. Inspect for fan to shroud interference, and any
damage to shroud such as cracks and holes.
•The fan ratio should not be changed and the fan spacer dimensions
and positions should not be altered.
•Inspect the fan clutch for proper operation, make sure that the fan is
disengaged when cooling of the engine is not required.
•Check for proper operation of radiator shutters, if equipped. The
shutters should be open during normal operating temperatures.
Engine and Driveline System
•Transmission Enclosure:inspect for cracks, holes, and tears. Clean
any deposits such as oil, dirt, and stones.
•Engine valve covers and block covers are made to damp out engine
mechanical noise and, if needed, should be replaced with
recommended parts. Check for mechanical isolations.
Exhaust System
•Inspect the exhaust system for leaks at various joint connections and
tighten the clamps.
•Do a visual inspection for cracks or holes in the muffler and tail pipe.
•Always use the recommended parts when items need to be replaced.
•The tail pipe elbow or offset tail pipe orientation must not be changed
from the standard position as originally received.
•To avoid abnormal changes in vehicle sound levels, it is necessary for
the owner to perform inspections and necessary maintenance at the
intervals shown in theGeneral Maintenance Informationsection.
CHASSIS-MOUNTED CHARGE AIR COOLER
Inspect charge air cooler daily
With the engine off, visually inspect the charge air cooler core assembly
for debris and clogging of external fins. Prior to engine operation,
remove any debris blocking the core.
•Turbocharger-to-charge air cooler
•Charge air cooler-to-intake manifold pipe
•Mounting bracket
•Chassis-mounted charge air cooler core
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Inspect air intake piping
•Check for accumulation of salt deposits (where applicable). If present,
disassemble and clean the complete air intake piping system. If the
intake piping is pitted, use RTV silicone to seal joints against leakage.
•Check for loose hoses and clamps.
•Check for ruptured or collapsed hoses.
•Check air cleaner housing for cracks.
ELECTRICAL SYSTEM INSPECTIONS
Periodically inspect electrical connectors on the outside of the cab, on
the engine and frame for corrosion and tightness. Exposed terminals
such as the fuel sender, cranking motor, alternator and feed-through
studs should be cleaned and re-coated with a lubricant sealing grease
such as Motorcraft XG-3, or equivalent. This should include the ground
cable connector for batteries, engine and cab as well as the jump starting
stud.
Accessory feed connections
Vehicle electrical systems are complex and often include electronic
components such as engine and transmission controls, instrument panels,
ABS, etc. While most systems operate on battery voltage (12 volts),
some systems can be as high as 90 volts or as low as five volts. Refer to
the Electrical Circuit Diagram Manuals, available from your vehicle’s
manufacturer, to assure that any additional body lights and accessories
are connected to circuits that are both appropriate and not overloaded.
No modification should be made to any vehicle control system without
first contacting your dealer.
SUSPENSION INSPECTION
Note:Do not adjust air suspension height to any setting other than the
specified setting. Altering the height setting will change the driveline
angle and may result in unwarrantable component damage, such as
transmission component damage.
Verify drive axle air suspension height and height control valve
performance at engine lube oil change intervals.
Periodically:
•Check condition of spring leaves for evidence of fatigue, bending or
breakage.
•Check condition of suspension mounting brackets and bushings.
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PROPELLER SHAFT
At the regular lubrication interval, check the universal joints for any
evidence of wear or looseness. Should propeller shaft vibrations occur,
stop the vehicle immediately to avoid possible hazardous consequences
or damage to other components.
REAR AXLE LUBRICANT
Refer to your general maintenance information section for rear axle
lubricant level checks and lubricant change intervals.
Your rear axle may be filled with an optional synthetic lubricant which
allows the use of extended service intervals. A tag on the filler plug will
identify the use of the synthetic lubricant.
Use only a lubricant that meets manufacturer specifications (refer to
Lubricant specificationsin this chapter).
Use of a non-approved rear axle lubricant may cause internal axle
component damage.
Check your rear axle lubricant level using the following procedure:
1. Park the vehicle on level ground.
2. Set the parking brake and shift into N (Neutral) (automatic
transmission) or 1 (First) (manual transmission) and turn the engine off.
3. Clean any dirt from around the rear axle filler plug.
4. Remove the filler plug and inspect the lubricant level.
5. The lubricant level should be up to the bottom of the filler plug
opening.
6. If necessary, add enough lubricant through the filler plug opening so
that the lubricant level is at the bottom of the opening.
7. Clean and install the filler plug securely.
Drain and refill your rear axle lubricant using the following procedure:
1. Drain the rear axle while the lubricant is warm.
2. Park the vehicle on level ground.
3. Set the parking brake and shift into N (Neutral) (automatic
transmission) or 1 (First) (manual transmission) and turn the engine off.
4. Clean any dirt from around the rear axle filler and drain plugs.
5. Remove the filler and drain plugs and drain the lubricant into a
suitable container. Dispose all used automotive fluids in a responsible
manner following your local authorized standards.
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