
Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse
Panel Description
F116 30A** Blower motor
F117 20A** Instrument panel power point
F118 30A** Heated seats
401 30A Circuit
breakerDelayed accessory power: Power
windows, Power sliding backlite
R01 Full ISO relay Starter solenoid
R02 Full ISO relay Accessory delay
R03 Full ISO relay Hi-beam headlamps
R04 Full ISO relay Heated backlite
R05 Full ISO relay Trailer tow battery charge
R06 Full ISO relay Blower motor
R201 Half ISO relay Trailer tow park lamps
R202 Half ISO relay Fog lamps
R203 Half ISO relay PCM
R301 Printed circuit
boardTrailer tow backup lamps
R302 — Not used
R303 Printed circuit
boardFuel pump
R304 Printed circuit
boardBattery saver
R305 Printed circuit
boardHorn
* Mini fuses ** Cartridge fuses
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
305

When checking the VIN look for the engine type identifier (8th
character). If your vehicle is an FFV, then the character will be
labeled as a “V”.
Pure ethanol is the alcohol which is the intoxicating agent in liquor, beer
and wine. It is distilled from the fermentation of plants such as field corn
and sugar cane. When ethanol is produced for use in motor fuels, a small
amount of gasoline is added to make it unfit for beverage use. The
resulting ethanol blend is called denatured fuel ethanol meaning that it is
denatured with 2% to 5% gasoline and is suitable for automotive use.
During the summer season, fuel ethanol may contain a maximum of 85%
denatured ethanol (Ed85) and 15% unleaded gasoline. The fuel ethanol
has a higher octane rating than unleaded regular or premium gasoline
and this allows the design of engines with greater efficiency and power.
Winter blends may contain up to 75% denatured ethanol (Ed75) and up
to 25% unleaded gasoline to enhance cold engine starts. Severely cold
weather may require additional measures for reliable starting. Refer to
Cold Weather Startingin theDrivingchapter.
Ethanol is more chemically active than gasoline. It corrodes some metals
and causes some plastic and rubber components to swell, break down or
become brittle and crack, especially when mixed with gasoline. Special
materials and procedures have been developed for flexible fuel vehicles
and the dispensers used by ethanol fuel providers.
Flexible fuel components and standard unleaded gasoline fuel
components are not interchangeable. If your vehicle is not
serviced in accordance with flexible fuel vehicles procedures, damage
may occur and your warranty may be invalidated.
When refueling always shut the engine off and never allow
sparks or open flames near the filler neck. Never smoke while
refueling. Fuel vapor is extremely hazardous under certain conditions.
Care should be taken to avoid inhaling excess fumes.
The flow of fuel through a fuel pump nozzle can produce static
electricity, which can cause a fire if fuel is pumped into an
ungrounded fuel container.
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
359

Refueling
Fuel vapor burns violently and a fuel fire can cause severe
injuries. To help avoid injuries to you and others:
•Read and follow all the instructions on the pump island;
•Turn off your engine when you are refueling;
•Do not smoke if you are near fuel or refueling your vehicle;
•Keep sparks, flames and smoking materials away from fuel;
•Stay outside your vehicle and do not leave the fuel pump unattended
when refueling your vehicle — this is against the law in some places;
•Keep children away from the fuel pump; never let children pump
fuel.
Use the following guidelines to avoid electrostatic charge build-up when
filling an ungrounded fuel container:
•Place approved fuel container on the ground.
•DO NOT fill a fuel container while it is in the vehicle (including the
cargo area).
•Keep the fuel pump nozzle in contact with the fuel container while
filling.
•DO NOT use a device that would hold the fuel pump handle in the fill
position.
Fuel Filler Cap
Your fuel tank filler cap has an indexed design with a 1/4 turn on/off
feature.
When fueling your vehicle:
1. Turn the engine off.
2. Carefully turn the filler cap counterclockwise 1/4 of a turn until it
stops.
3. Pull to remove the cap from the fuel filler pipe.
4. To install the cap, align the tabs on the cap with the notches on the
filler pipe.
5. Turn the filler cap clockwise 1/4 of a turn until it clicks at least once.
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
360

Octane recommendations
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.
Unleaded Gasoline Engines
Your vehicle is designed to use “Regular” unleaded gasoline with an
(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.
FFV engine (if equipped)
Your vehicle is designed to use Fuel Ethanol (Ed75–Ed85),“Regular”
unleaded gasoline or any mixture of the two fuels.
U.S. government regulations require fuel ethanol dispensing
pumps to have a small, square, orange and black label with the
common abbreviation or the appropriate percentage for that
region. Use of other fuels such as Fuel Methanol may cause
powertrain damage, a loss of vehicle performance, and your
warranty may be invalidated.
Fuel quality
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.
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.
87(R+M)/2 METHOD
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
363

Unleaded Gasoline engines
If you are experiencing starting, rough idle or hesitation driveability
problems during a cold start, try a different brand of “Regular” unleaded
gasoline. “Premium” unleaded gasoline is not recommended because it
may cause these problems to become more pronounced. If the problems
persist, see your authorized dealer.
FFV engine (if equipped)
To identify if your vehicle is an FFV, it may be equipped with a yellow
fuel cap with the writing “E85/Gasoline”, or check if there is a label on
the fuel filler door, or check your VIN. When checking the VIN, look for
the engine type identifier (8th character). If your vehicle is an FFV, then
the character will be labeled as a “V”.
It is best not to alternate repeatedly between gasoline and E
85. If you do
switch fuels, it is recommended that you add as much fuel as
possible—at least half a tank. Do not add less than five gallons (18.9 L)
when refueling. You should drive the vehicle immediately after refueling
for at least five miles (8 km) to allow the vehicle to adapt to the change
in ethanol concentration.
If you operate your vehicle 50% or more of the time on ethanol, you
should follow a different maintenance schedule. In addition to this it is
also recommended to fill the fuel tank with regular unleaded gasoline
once every 3,000 miles (4,828 km). Seescheduled maintenance
informationfor more information.
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.
•TheService engine soon
indicator may come on. For more
information on theService engine soon
indicator, refer to
Warning lights and chimesin theInstrument Clusterchapter.
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
364

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 switch to the off position prior to refueling,
an error in the reading may 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 three 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).
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
365

idle speed control ...................349
lubrication specifications .......381
refill capacities ........................381
service points ..................341–343
starting after a collision .........298
Engine block heater .................262
Engine oil ..................................345
checking and adding ..............345
dipstick ....................................345
filter, specifications ........348, 380
recommendations ...................348
refill capacities ........................381
specifications ..........................381
Event data recording ....................7
Exhaust fumes ..........................262
F
Fail safe cooling ........................356
Family entertainment system ....51
Flexible Fuel Vehicle (FFV) ....357
Floor mats .................................134
Fluid capacities .........................381
Foglamps .....................................92
Four-Wheel Drive vehicles .......282
driving off road .......................286
electronic shift ................284–285
indicator light .........................282
lever operated shift ................283
preparing to drive your
vehicle .....................................268
Fuel ............................................357
calculating fuel
economy ..........................128, 365
cap ...........................................360
capacity ...................................381
choosing the right fuel ...........362comparisons with EPA fuel
economy estimates .................367
detergent in fuel .....................362
filling your vehicle
with fuel ..................357, 360, 365
filter, specifications ........357, 380
fuel pump shut-off switch .....298
improving fuel economy ........365
octane rating ...................363, 385
quality ..............................363–364
running out of fuel .................364
safety information relating
to automotive fuels ................357
Fuel - flex fuel vehicle
(FFV) .........................357, 362–363
Fuel pump shut-off switch .......298
Fuses ..................................299–300
G
Gas cap (see Fuel cap) ............360
Gas mileage
(see Fuel economy) .................365
Gauges .........................................20
H
Hazard flashers .........................298
Head restraints .................158, 162
Headlamps ...................................91
aiming ..................................93–94
autolamp system .......................91
bulb specifications ....................97
daytime running lights .............92
flash to pass ..............................92
high beam .................................92
replacing bulbs .........................98
turning on and off ....................91
Heating
heater only system ...................81
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Index
393