
Fuse/Relay
LocationFuse Amp
RatingProtected Circuits
11 10A Not used (spare)
12 7.5A Power mirror switch, Driver power
seat (Memory)
13 5A Not used (spare)
14 10A Upfitter relay #3 feed
15 10A Climate control head
16 15A Upfitter relay #4 Feed
17 20A All lock motor feeds
18 20A Heated seat relay feed
19 25A Not used (spare)
20 15A Adjustable pedals, Datalink
21 15A Fog lamp relay feed, Cornering lamps
22 15A Park lamp relay feed
23 15A High beam headlight relay feed
24 20A Horn relay feed
25 10A Power telescoping mirror switch,
Demand lamps - underhood and
illuminated visor (battery saver)
26 10A Cluster
27 20A Ignition switch feed, Passenger
compartment fuses 28, 42, 43, 44, and
45, Engine compartment starter relay
coil #57 (Diesel engine), Accessory
shutoff control module (if equipped)
(Diesel engine), Engine compartment
starter relay diode (gasoline engines)
28 5A Radio
29 5A Not used (spare)
30 5A Not used (spare)
31 10A Not used (spare)
32 10A Restraints control module (RCM),
Passenger airbag deactivation
indicator
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Fuse/Relay
LocationFuse Amp
RatingProtected Circuits
53 Relay PCM power bus (Fuses 68, 70, 72,
74, 76) (Diesel engine only)
54 Relay Starter solenoid
55 Relay Trailer tow park lamps
56 Relay Trailer tow battery charge
57 Relay Power Distribution Box (PDB) bus
(fuses 67, 69, 71, 73, 75, 77)
SJB Run /Start bus (Fuses 29–37, 46)
58 Relay ESOF hi-lo
59 Relay PCM power bus (Fuses 68, 70, 72,
74, 76) (Gasoline engines only)
60 Diode One-touch start (OTIS)
61 Diode A/C clutch
62 Diode Fuel pump
63 15A** Trailer tow back-up lamps
64 5A** Mirror marker lamps
65 — Not used
66 — Not used
67 — Not used
68 — Not used
69 — Not used
70 10A**Gasoline engines:A/C clutch relay
coil, Refrigerant containment switch,
Heated PCV
Diesel engine:A/C clutch relay coil,
Clutch switch, Fuel pump cooler, A/C
cycle pressure switch
71 5A** Fuel pump relay diode, PCM/ECM
Run/Start power
72 15A**Gasoline engines:Ignition coils
Diesel engine:Engine TCM
73 2A** Reverse Camera System (RCS)
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ENGINE
Engines are more efficient when they are clean because grease and dirt
buildup keep the engine warmer than normal. When washing:
•Take care when using a power washer to clean the engine. The
high-pressure fluid could penetrate the sealed parts and cause
damage.
•Do not spray a hot engine with cold water to avoid cracking the
engine block or other engine components.
•Spray MotorcraftEngine Shampoo and Degreaser (ZC-20) on all
parts that require cleaning and pressure rinse clean.
•Never wash or rinse the engine while it is running; water in the
running engine may cause internal damage.
•Never wash or rinse any ignition coil, spark plug wire or spark plug
well, or the area in and around these locations.
•Cover the highlighted areas to prevent water damage when cleaning
the engine.
•5.4L V8 gasoline engine
Cleaning
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Running out of fuel
Avoid running out of fuel because this situation may have an adverse
effect on powertrain components.
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 1 gallon (3.8L) of fuel is enough to restart the
engine. If the vehicle is out of fuel and on a steep grade, more than
1 gallon (3.8L) may be required.
•The service engine soon
indicator may come on. For more
information on the service engine soon
indicator, refer to
Warning lights and chimesin 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.
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For consistent results when filling the fuel tank:
•Turn the engine/ignition switch to the off position prior to refueling,
an error in the reading will result if the engine is left running.
•Use the same filling rate setting (low — medium — high) each time
the tank is filled.
•Allow no more than two 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.
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•Adding certain accessories to your vehicle (for example bug
deflectors, rollbars/light bars, running boards, ski/luggage racks) may
reduce fuel economy.
•To maximize the fuel economy, drive with the tonneau cover installed
(if equipped).
•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 fuel economy estimates
If applicable, every new vehicle should have a sticker on the window
called the Monroney Label which contains EPA fuel economy estimates.
Contact your authorized dealer if the Monroney Label is not supplied
with your vehicle. The EPA fuel economy estimates should be your guide
for the fuel economy comparisons with other vehicles. 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 inscheduled maintenance information
performed according to the specified schedule.
The scheduled maintenance items listed inscheduled maintenance
informationare essential to the life and performance of your vehicle
and to its emissions system.
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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.
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 service engine soon
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 service engine soon
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 service engine soon
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
Some state/provincial and local governments may have
Inspection/Maintenance (I/M) programs to inspect the emission control
equipment on your vehicle. Failure to pass this inspection could prevent
you from getting a vehicle registration. Your vehicle may not pass the I/M
test if the service engine soon
indicator is on or not working
properly (bulb is burned out), or if the OBD-II system has determined
that some of the emission control systems have not been properly
checked. In this case, the vehicle is considered not ready for I/M testing.
If the service engine soon
indicator is on or the bulb does not
work, the vehicle may need to be serviced. Refer to the On board
diagnostics (OBD-II) description in this chapter.
If the vehicle’s engine or transmission has just been serviced, or the
battery has recently run down or been replaced, the OBD-II system may
indicate that the vehicle is not ready for I/M testing. To determine if the
vehicle is ready for I/M testing, turn the ignition key to the on position
for 15 seconds without cranking the engine. If the service engine
soon
indicator blinks eight times, it means that the vehicle is not
ready for I/M testing; if the service engine soon
indicator stays on
solid, it means that the vehicle is ready for I/M testing.
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ENGINE DATA
Engine 5.4L V8 engine 6.8L V10 engine
Cubic inches 330 415
Required fuel 87 octane 87 octane
Firing order 1-3-7-2-6-5-4-8 1-6-5-10-2-7-3-8-4-9
Spark plug gap1.0–1.1mm
(0.039–0.043 inch)1.0–1.1mm
(0.039–0.043 inch)
Ignition system Coil on plug Coil on plug
Compression ratio 9.8:1 9.2:1
Drivebelt routing
5.4L V8/6.8L V10 engines
Maintenance and Specifications
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