
* Heavy duty trailer towing with ambient temperatures above 50°F
(10°C) requires 15W-40 engine oil.
Using the chart, determine which SAE viscosity grade best suits the
temperature range in which you expect to operate your vehicle. The use
of the correct oil viscosity grade for diesel engines is important for
satisfactory engine operation.
A symbol has been developed by the American Petroleum Institute (API)
to help you select the proper engine oil. The symbol will be included on
the oil container you purchase.
The top section of the symbol shows
the API service category
designation. This should be CI-4/SL
or CI-4 PLUS.
The center section of the API
symbol shows the SAE viscosity
grade.
Use a Ford engine oil filter, part number FL-1995 or equivalent. This
filter protects your engine by filtering harmful, abrasive or sludge
particles.
SAE VISCOSITY GRADES
EXPECTED TEMPERATURE RANGE
F˚ -20 -10 0 10 20 30 40
40 35 30 25 20 15 10 5 0 -5 -10 -15 -20 -25 -30 C˚50 60 70 80 90 100
*15W-40 Preferred
10W-30
5W-30
0W-30Preferred
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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 INFORMATION
Important safety precautions
Do not overfill the fuel tank. The pressure in an overfilled tank
may cause leakage and lead to fuel spray and fire.
The fuel system may be under pressure. If the fuel cap is venting
vapor or if you hear a hissing sound, wait until it stops before
completely removing the cap.
Automotive fuels can cause serious injury or death if misused or
mishandled.
Observe the following guidelines when handling fuel:
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•Extinguish all smoking materials
and any open flames before
fueling your vehicle.
•Always turn off the vehicle before
fueling.
•Automotive fuels can be harmful
or fatal if swallowed. If fuel is swallowed, call a physician immediately,
even if no symptoms are immediately apparent. The toxic effects of
fuel may not be visible for hours.
•Avoid inhaling fuel vapors. Inhaling too much fuel vapor of any kind
can lead to eye and respiratory tract irritation. In severe cases,
excessive or prolonged breathing of fuel vapor can cause serious
illness and permanent injury.
•Avoid getting fuel liquid in your eyes. If fuel is splashed in the eyes,
remove contact lenses (if worn), flush with water for 15 minutes and
seek medical attention. Failure to seek proper medical attention could
lead to permanent injury.
•Fuels can also be harmful if absorbed through the skin. If fuel is
splashed on the skin and/or clothing, promptly remove contaminated
clothing and wash skin thoroughly with soap and water. Repeated or
prolonged skin contact with fuel liquid or vapor causes skin irritation.
If you must replace the fuel filler cap, replace it with a genuine
Ford or Motorcraft part. The customer warranty may be void for
any damage to the fuel tank or fuel system if a genuine Ford or
Motorcraft fuel filler cap is not used.
If you do not use the proper fuel filler cap, excessive pressure or
vacuum in the fuel tank may damage the fuel system or cause
the fuel cap to disengage in a collision, which may result in possible
personal injury.
Choosing the right fuel
The engine is designed to use low sulfur number 1D or 2D diesel fuel
only. At temperatures below –20°F (–7°C), number 1D or winter blend
number 2D fuel is recommended. (SeeCold weather operationin the
Drivingsection.) Diesel fuel containing no more than 5% of biodiesel
may be used. Biodiesel fuel is a product derived from renewable fuel
sources such as vegetable oil, animal fat and cooking oil.
Do not use home heating oil or any diesel fuel not intended for
highway use. Red dye is used to identify fuels intended for
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agricultural and non-highway use. Damage to the fuel injection
system, engine and exhaust catalyst can occur if an improper fuel
is used. Do not add gasoline, gasohol or alcohol to diesel fuel.
This practice creates a serious fire hazard and engine
performance problems.
Use low sulfur (less than 0.05% by weight) fuel as required by the EPA
for emission compliance.
Do not mix diesel fuel with gasoline, gasohol or alcohol. This
could cause an explosion resulting in personal injury.
Do not use starting fluid such as ether or gasoline. Such fluids
can cause immediate explosive damage to the engine and
possible personal injury.
Fuel quality
It should not be necessary to add any aftermarket additives to your fuel
tank if you use a properly formulated diesel fuel that meets ASTM D 975
specification. Aftermarket additives can damage the injector system or
engine. Repairs to correct the effects of using an aftermarket product in
your fuel may not be covered by your warranty.
Do not blend used engine oil with diesel fuel under any
circumstances.Blending used oil with the fuel will significantly increase
your vehicle’s exhaust emissions and reduce engine life due to increased
internal wear.
Many of the world’s automakers approved the World-wide Fuel Charter
that recommends diesel fuel specifications to provide improved
performance and emission control system protection for your vehicle.
Diesel fuel that meet the World-wide Fuel Charter should be used when
available. Ask your fuel supplier about fuel that meet the World-Wide
Fuel Charter.
Running out of fuel
Avoid running out of fuel as this will allow air to enter the fuel system,
which will make restarting the vehicle difficult.
If you have run out of fuel:
•If your vehicle is equipped with dual fuel tanks,add at least 4–5
gallons (15–19 liters) of fuel to each tank before attempting to restart
the engine.
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Air Intake System
•Air Cleaner:should be inspected and its location should not be
altered. Do not alter inlet and outlet piping.
Body
•Wheel Well:splash shields, cab shields and under-hood insulation
should be inspected for deterioration, dislocation, and orientation.
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 theScheduled Maintenance Guidechapter.
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.
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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.
•Check that torque rod mounting fasteners are tight.
•Check to be sure the suspension alignment is maintained at all time.
•Check U-bolts after the chassis has been operating under load for
1,000 miles (1,600 km) or six months, whichever comes first, the
U-Bolt nuts must be re-torqued. The U-Bolt nuts thereafter must be
re-torqued every 36,000 miles (58,000 km). The U-Bolt and nut
threads and seats should be cleaned and lubricated to ensure a “like
new” condition when re-torquing.
Note:See theU-Bolt Nut Torquechart later in this section.
Supporting your vehicle for service
When performing service repairs on your vehicle, first prepare the
vehicle by doing the following:
1. Park the vehicle on a level concrete floor.
2. Set the parking brake and block the wheels to prevent the vehicle
from moving.
3. Select a jack with a rated capacity sufficient to lift and hold up the
vehicle.
4. Raise the vehicle with the jack applied to the axle(s). DO NOT use the
bumper as a lifting point.
5. Support the vehicle with floor stands under the axle(s). If the axle or
the suspension are being serviced, support the vehicle with floor stands
under the frame side-members, preferably between the axles.
Do not use a jack when working under a vehicle. It may give
way, causing the vehicle to fall and result in property damage,
personal injury or death. Always use floor stands to support the
vehicle.
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Draining and refilling the rear axle lubricant
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 of all used automotive fluids in a responsible
manner following your local authorized standards.
6. Clean and install the drain plug securely.
7. Add enough lubricant through the filler plug opening so that the
lubricant level is up to the bottom of the opening.
8. Clean and install the filler plug securely.
WHEELS
General
Wheel bearings should be inspected, lubricated and adjusted at regular
intervals. This is especially important if operating in deep sand, mud, or
water. Refer toLubricant specificationsin this chapter.
When installing wheel balance weights, they must be mounted on the
dome-side of the wheel only. Failure to do so may result in loss of wheel
weight and/or damage to brakes or wheels.
Important:Remember to replace the wheel air valves when the road
tires are replaced at the end of their useful life.
Oil lubricated front wheel bearings
During normal vehicle duty cycle, the lube and air inside the hub/wheel
cavity expands and if not vented, causes pressure build-up that could
cause accelerated seal wear.
There are two venting methods:
•a slit or small hole in the rubber check vent or
•the window
You can use either of these methods to prevent pressure build-up.
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Normal maintenance
Over a period of time, if not routinely cleaned, a slight film of oil can
collect dirt around the rubber fill plug and face, which could appear to
be a leak. Routine cleaning ensures that the lube level can be easily
observed through the clear window as intended. In situations where the
window is clean on the outside but discolored on the inside, the lube
level may be checked by inserting a finger through the rubber check
vent hole.
The specified lube level for a clear window type hubcaps is from the
minimum line to + 5/16 inch above the minimum line.
If the lube level should suddenly drop dramatically below the minimum
level, see the Service Manual for diagnostic procedure.
Installation, tightening and alignment
8–lug wheel
10–lug wheel
When installing wheels, be certain that the threads on studs and nuts are
clean to permit correct torquing of nuts. The mounting surfaces of rims,
wheels, spacer rings and clamps must be free of dirt, rust, lubricants or
damage.
Use a wire brush to clean the mounting contact surfaces. Do not use
lubricant on threads.
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