2008 FORD SUPER DUTY fuel

Octane recommendations
Your vehicle is designed to use
“Regular” unleaded gasoline with
pump (R+M)/2 octane rating of 87.
We do not recommend the use of
gasolines labeled as “Regular” that
are sold with octane ratings of 86 or lower in high altitude areas.
Do not be concerned if your engine sometimes knocks lightly. However, if
it knocks heavily under most driving conditions while you are using fuel
with the recommended octane rating, see your authorized dealer to
prevent any engine damage.
Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems, try a different brand of unleaded gasoline. “Premium”
unleaded gasoline is not recommended for vehicles designed to use
“Regular” unleaded gasoline because it may cause these problems to
become more pronounced. If the problems persist, see your authorized
dealer.
Do not add aftermarket fuel additive products to your fuel tank. It
should not be necessary to add any aftermarket products to your fuel
tank if you continue to use high quality fuel of the recommended octane
rating. These products have not been approved for your engine and
could cause damage to the fuel system. Repairs to correct the effects of
using an aftermarket product in your fuel may not be covered by your
warranty.
Many of the world’s automakers approved the World-wide Fuel Charter
that recommends gasoline specifications to provide improved
performance and emission control system protection for your vehicle.
Gasolines that meet the World-wide Fuel Charter should be used when
available. Ask your fuel supplier about gasolines that meet the
World-wide Fuel Charter.
Cleaner air
Ford endorses the use of reformulated “cleaner-burning” gasolines to
improve air quality, per the fuel recommendations in theChoosing the
right fuelsection.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
affect on powertrain components.
87(R+M)/2 METHOD
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If you have run out of fuel:
•You may need to cycle the ignition from OFF to ON several times after
refueling to allow the fuel system to pump the fuel from the tank to
the engine. On restarting, cranking time will take a few seconds longer
than normal.
•Normally, adding one gallon of fuel is enough to restart the engine. If
the vehicle is out of fuel and on a steep grade, more than one gallon
may be required.
•TheCheck engineindicator (
) may come on. For more
information on theCheck engineindicator, refer to theInstrument
Clusterchapter.
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 1,000 miles
(1,600 km) of driving (engine break-in period). You will get a more
accurate measurement after 2,000 miles-3,000 miles
(3,000 km–5,000 km).
Filling the tank
The advertised fuel capacity of the fuel tank on your vehicle is equal to
the rated refill capacity of the fuel tank as listed in theMaintenance
Product Specifications and Capacitiessection of 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 fuel remaining in the fuel
tank after the fuel gauge indicates empty.
The amount of usable fuel in the 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.
For consistent results when filling the fuel tank:
•Turn the engine/ignition off prior to refueling, an error in the reading
will result if the engine is left running.
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•Use the same filling rate setting (low-medium-high) each time the
tank is filled.
•Allow no more than 2 automatic click-offs when filling.
•Always use fuel with the recommended octane rating.
•Use a known quality gasoline, preferably a national brand.
•Use the same side of the same pump and have the vehicle facing the
same direction each time you fill up.
•Have the vehicle loading and distribution the same every time.
Your results will be most accurate if your filling method is consistent.
Calculating fuel economy
1. Fill the fuel tank completely and record the initial odometer reading
(in miles or kilometers).
2. Each time you fill the tank, record the amount of fuel added (in
gallons or liters).
3. After at least three to five tank fill-ups, fill the fuel tank 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:
Calculation 1:Divide total miles traveled by total gallons used.
Calculation 2:Multiply liters used by 100, then divide by total
kilometers traveled.
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.
Driving style — good driving and fuel economy habits
Give consideration to the lists that follow and you may be able to change
a number of variables and improve your fuel economy.
Habits
•Smooth, moderate operation can yield up to 10% savings in fuel.
•Steady speeds without stopping will usually give the best fuel
economy.
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•Idling for long periods of time (greater than one minute) may waste
fuel.
•Anticipate stopping; slowing down may eliminate the need to stop.
•Sudden or hard accelerations may reduce fuel economy.
•Slow down gradually.
•Driving at reasonable speeds (traveling at 55 mph [88 km/h] uses 15%
less fuel than traveling at 65 mph [105 km/h]).
•Revving the engine before turning it off may reduce fuel economy.
•Using the air conditioner or defroster may reduce fuel economy.
•You may want to turn off the speed control in hilly terrain if
unnecessary shifting between third and fourth gear occurs.
Unnecessary shifting of this type could result in reduced fuel
economy.
•Warming up a vehicle on cold mornings is not required and may
reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
•Combine errands and minimize stop-and-go driving.
Maintenance
•Keep tires properly inflated and use only recommended size.
•Operating a vehicle with the wheels out of alignment will reduce fuel
economy.
•Use recommended engine oil. Refer toMaintenance Product
Specifications and Capacitiesin this chapter.
•Perform all regularly scheduled maintenance items. Follow the
recommended maintenance schedule and owner maintenance checks
found in your vehicle’sscheduled maintenance information.
Conditions
•Heavily loading a vehicle or towing a trailer may reduce fuel economy
at any speed.
•Carrying unnecessary weight may reduce fuel economy (approximately
1 mpg [0.4 km/L] is lost for every 400 lb [180 kg] of weight carried).
•Adding certain accessories to your vehicle (for example bug
deflectors, rollbars/light bars, running boards, ski/luggage racks) may
reduce fuel economy.
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•Using fuel blended with alcohol may lower fuel economy.
•Fuel economy may decrease with lower temperatures during the first
8–10 miles (12–16 km) of driving.
•Driving on flat terrain offers improved fuel economy as compared to
driving on hilly terrain.
•Transmissions give their best fuel economy when operated in the top
cruise gear and with steady pressure on the gas pedal.
•Four-wheel-drive operation (if equipped) is less fuel efficient than
two-wheel-drive operation.
•Close windows for high speed driving.
EPA window sticker
Every new vehicle should have the EPA window sticker. Contact your
authorized dealer if the window sticker is not supplied with your vehicle.
The EPA window sticker should be your guide for the fuel economy
comparisons with other vehicles.
It is important to note the box in the lower left corner of the window
sticker. These numbers represent the Range of MPG (L/100 km)
expected on the vehicle under optimum conditions. Your fuel economy
may vary depending upon the method of operation and conditions.
EMISSION CONTROL SYSTEM
Your vehicle is equipped with various emission control components and a
catalytic converter which will enable your vehicle to comply with
applicable exhaust emission standards. To make sure that the catalytic
converter and other emission control components continue to work
properly:
•Use only the specified fuel listed.
•Avoid running out of fuel.
•Do not turn off the ignition while your vehicle is moving, especially at
high speeds.
•Have the items listed in yourscheduled maintenance information
performed according to the specified schedule.
The scheduled maintenance items listed in thescheduled maintenance
informationare essential to the life and performance of your vehicle
and to its emissions system.
If other than Ford, Motorcraft or Ford-authorized parts are used for
maintenance replacements or for service of components affecting
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emission control, such non-Ford parts should be equivalent to genuine
Ford Motor Company parts in performance and durability.
Do not park, idle, or drive your vehicle in dry grass or other dry
ground cover. The emission system heats up the engine
compartment and exhaust system, which can start a fire.
Illumination of theCheck enginelight (
), charging system warning
light or the temperature warning light, fluid leaks, strange odors, smoke
or loss of engine power, could indicate that the emission control system
is not working properly.
Exhaust leaks may result in entry of harmful and potentially
lethal fumes into the passenger compartment.
Do not make any unauthorized changes to your vehicle or engine. By
law, vehicle owners and anyone who manufactures, repairs, services,
sells, leases, trades vehicles, or supervises a fleet of vehicles are not
permitted to intentionally remove an emission control device or prevent
it from working. Information about your vehicle’s emission system is on
the Vehicle Emission Control Information Decal located on or near the
engine. This decal identifies engine displacement and gives some tune up
specifications.
Please consult yourWarranty Guidefor complete emission warranty
information.
On board diagnostics (OBD-II)
Your vehicle is equipped with a computer that monitors the engine’s
emission control system. This system is commonly known as the On
Board Diagnostics System (OBD-II). The OBD-II system protects the
environment by ensuring that your vehicle continues to meet
government emission standards. The OBD-II system also assists your
authorized dealer in properly servicing your vehicle. When the
indicator illuminates, the OBD-II system has detected a malfunction.
Temporary malfunctions may cause the
indicator to illuminate.
Examples are:
1. The vehicle has run out of fuel - the engine may misfire or run poorly.
2. Poor fuel quality or water in the fuel - the engine may misfire or run
poorly.
3. The fuel cap may not have been securely tightened. SeeFuel filler
capin this chapter.
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4. Driving through deep water - the electrical system may be wet.
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel, properly tightening the fuel cap or letting the
electrical system dry out. After three driving cycles without these or any
other temporary malfunctions present, the
indicator should stay off
the next time the engine is started. A driving cycle consists of a cold
engine startup followed by mixed city/highway driving. No additional
vehicle service is required.
If the
indicator remains on, have your vehicle serviced at the first
available opportunity. Although some malfunctions detected by the
OBD-II may not have symptoms that are apparent, continued driving
with the
indicator on can result in increased emissions, lower fuel
economy, reduced engine and transmission smoothness, and lead to more
costly repairs.
Readiness for Inspection/Maintenance (I/M) testing
In some localities, it may be a legal requirement to pass an I/M test of
the on-board diagnostics system. If the
indicator is on, refer to the
description in the Warning lights and chimes section of the Instrument
Cluster chapter. Your vehicle may not pass the I/M test with the
indicator on.
If the vehicle’s powertrain system or its battery has just been serviced,
the on-board diagnostics system is reset to a “not ready for I/M test”
condition. To ready the on-board diagnostics system for I/M testing, a
minimum of 30 minutes of city and highway driving is necessary as
described below:
•First, at least 10 minutes of driving on an expressway or highway.
•Next, at least 20 minutes driving in stop-and-go, city-type traffic with
at least four idle periods.
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete.
POWER STEERING FLUID
Check the power steering fluid. Refer to thescheduled maintenance
informationfor the service interval schedules. If adding fluid is
necessary, use only MERCON
AT F.
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5. Return air filter cover to original
position making sure the four tabs
are engaged and secure the three
clamps. Tighten clamp on air tube
and reconnect sensor.
MOTORCRAFT PART NUMBERS
Component 5.4L V8/6.8L V10 engines
Air filter element FA-1883
Fuel filter FG-1011
Oil filter FL-820-S
PCV valve
1
Battery (Standard) BXT-65-650
Battery (Optional) BXT-65-750
Spark plugs-platinum
2
Remote Automatic Transmission Filter3, 4
1
The PCV valve is a critical emission component. It is one of the items
listed in thescheduled maintenance informationand is essential to
the life and performance of your vehicle and to its emissions system.
For PCV valve replacement, see your authorized dealer. Refer to the
scheduled maintenance informationfor the appropriate intervals for
changing the PCV valve.
Replace the PCV valve with one that meets Ford material and
design specifications for your vehicle, such as a Motorcraft or
equivalent replacement part. The customer warranty may be void
for any damage to the emissions system if such a PCV valve is not
used.
2For spark plug replacement, see your authorized dealer. Refer to the
scheduled maintenance informationfor the appropriate intervals for
changing the spark plugs.
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