2021 FORD F-250 light

III (start) - Cranks the engine.
KEYLESS STARTING
(IF EQUIPPED)
Note: The keyless starting system may not
function if the key is close to metal objects
or electronic devices such as cellular
phones.
Note: A valid key must be located inside
your vehicle to switch the ignition on and
start the engine. The keyless starting system has three
modes:
Off:
Turns the ignition off.
• Without applying the clutch pedal for
manual transmissions, or brake pedal
for automatic transmissions, press and
release the button once when the
ignition is in the on mode, or when the
engine is running but the vehicle is not
moving.
On:
All electrical circuits are operational
and the warning lamps and indicators
illuminate.
• Without applying the clutch pedal for
manual transmissions, or brake pedal
for automatic transmissions, press and
release the button once.
Start:
Starts the vehicle. •
Press the clutch pedal for manual
transmissions, or brake pedal for
automatic transmissions, and then
press the button for any length of time.
An indicator light on the button
illuminates when then ignition is on and
when the engine starts.
STARTING A GASOLINE
ENGINE - 6.2L/7.3L
When you start the engine, the idle speed
increases. This helps to warm up the
engine.
If the engine idle speed does not slow
down, see an authorized dealer.
Before starting the engine check the
following:
• Make sure all occupants fasten their
seat belt.
• Make sure the headlamps and
electrical accessories are off.
• Make sure the parking brake is on.
• Make sure the transmission is in park
(P).
• Turn the ignition key to the on position.
Note: Do not touch the accelerator pedal.
1. Fully press the brake pedal.
2. Turn the key to the start position to start your vehicle.
3. When the engine starts, release the key
and then gradually release the brake
pedal as the engine speed increases.
Note: The engine may continue cranking
for up to 15 seconds or until it starts.
Note: If you cannot start the engine on the
first try, wait for a short period and try again.
Vehicles with an Ignition Key
Note: Do not touch the accelerator pedal.
1. Fully press the brake pedal.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Starting and Stopping the EngineE144447

Automatic Engine Shutdown
If your vehicle is equipped with a keyless
ignition, it has a feature that automatically
shuts down the engine if it has been idling
for an extended period. The ignition also
turns off in order to save battery power.
Before the engine shuts down, a message
appears in the information display showing
a timer counting down from 30 seconds.
If you do not intervene within 30 seconds,
the engine shuts down. Another message
appears in the information display to
inform you that the engine has shut down
in order to save fuel. Start your vehicle as
you normally do.
Cold Weather Starting
WARNING: Do not use starting
fluid, for example ether, in the air intake
system. Such fluid could cause
immediate explosive damage to the
engine and possible personal injury. WARNING:
Do not mix diesel with
gasoline, gasohol or alcohol. This could
cause an explosion.
We recommend that the engine block
heater be used for starting when the
temperature is -9°F (-23°C) or colder. See
Engine Block Heater
(page 182).
When operating in cold weather, you may
use Motorcraft® cetane improvers or
non-alcohol-based cetane improvers from
a reputable manufacturer as needed. Switch the ignition on. Do not
start the engine until the
glow-plug indicator turns off. When the glow plug pre-heat indicator
turns off, turn the key to start. After you
start the engine, the glow plugs may
remain on for a period. If you do not start
the engine before the glow plug activation
time ends, you need to reset the glow plugs
by switching the ignition off. After the
engine starts, allow it to idle for about 15
seconds. This protects the engine. Do not
increase engine speed until the oil pressure
gauge indicates normal pressure.
Cold Weather Operation
Note:
Idling in cold weather does not heat
the engine to its normal operating
temperature. Long periods of idling,
especially in cold weather, can cause a
buildup of deposits which can cause engine
damage.
Change to a lighter grade engine oil to
make starting easier under these
conditions. Refer to engine oil
specifications. See
Engine Oil Capacity
and Specification (page 449).
Diesel fuel is adjusted seasonally for cold
temperatures. Diesel fuel which has not
been properly formulated for the ambient
conditions may gel which can clog the fuel
filters. One indication that the fuel filter(s)
may be clogged is if the engine starts, stalls
after a short time, and then does not
restart. If you have been using biodiesel,
you may need to use a fuel with lower
biodiesel content, try another brand, or
discontinue using biodiesel. Do not use
alcohol based additives to correct fuel
gelling. This may result in damage to the
fuel injectors and system. Use the proper
anti-gel and performance improvement
product. See
Engine Oil Capacity and
Specification (page 449).
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Starting and Stopping the Engine

FUEL QUALITY - E85
Choosing the Right Fuel - Flex Fuel
Vehicles
Flex fuel vehicles have one of the following
identifiers:
•
Yellow fuel filler cap.
• Yellow bezel around the fuel filler inlet.
• Yellow fuel filler housing.
• Yellow E85 label on the fuel tank filler
door. Your vehicle is designed to operate on
regular unleaded gasoline with a minimum
pump (R+M)/2 octane rating of 87 or
regular unleaded gasoline blended with a
maximum of 85% ethanol (E85).
Some fuel stations, particularly those in
high altitude areas, offer fuels posted as
regular unleaded gasoline with an octane
rating below 87. The use of these fuels
could result in engine damage that will not
be covered by the vehicle warranty.
For best overall vehicle and engine
performance, premium fuel with an octane
rating of 91 or higher is recommended. The
performance gained by using premium fuel
is most noticeable in hot weather as well
as other conditions, for example when
towing a trailer. See Towing (page 282).Do not be concerned if the engine
sometimes knocks lightly. However, if the
engine knocks heavily while using fuel with
the recommended octane rating, contact
an authorized dealer to prevent any engine
damage.
We recommend Top Tier detergent
gasolines, where available to help minimize
engine deposits and maintain optimal
vehicle and engine performance. For
additional information, refer to
www.toptiergas.com.
Note:
Use of any fuel for which the vehicle
was not designed can impair the emission
control system, cause loss of vehicle
performance, and cause damage to the
engine which may not be covered by the
vehicle Warranty.
Do not use:
• Diesel fuel.
• Fuels containing kerosene or paraffin.
• Fuels containing more than 85%
ethanol or E100 fuel.
• Fuels containing methanol.
• Fuels containing metallic-based
additives, including manganese-based
compounds.
• Fuels containing the octane booster
additive, methylcyclopentadienyl
manganese tricarbonyl (MMT).
• Leaded fuel, using leaded fuel is
prohibited by law.
The use of fuels with metallic compounds
such as methylcyclopentadienyl
manganese tricarbonyl (commonly known
as MMT), which is a manganese-based
fuel additive, will impair engine
performance and affect the emission
control system.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Fuel and RefuelingE161513

Switching Between E85 and
Gasoline
We do not recommend repeatedly
alternating between E85 and gasoline. If
you switch from using E85 to gasoline, or
from gasoline to E85, add as much fuel as
possible, at least half a tank. Drive your
vehicle immediately for a minimum of 5 mi
(8 km) to allow it to adapt to the change
in ethanol concentration. If you use E85
exclusively, we recommend that you fill
the fuel tank with regular unleaded
gasoline at each scheduled oil change.
FUEL QUALITY - GASOLINE
Choosing the Right Fuel Your vehicle is designed to operate on
regular unleaded gasoline with a minimum
pump (R+M)/2 octane rating of 87.
Some fuel stations, particularly those in
high altitude areas, offer fuels posted as
regular unleaded gasoline with an octane
rating below 87. The use of these fuels
could result in engine damage that will not
be covered by the vehicle warranty.
For best overall vehicle and engine
performance, premium fuel with an octane
rating of 91 or higher is recommended. The
performance gained by using premium fuel
is most noticeable in hot weather as well
as other conditions, for example when
towing a trailer. See
Towing (page 282). Do not be concerned if the engine
sometimes knocks lightly. However, if the
engine knocks heavily while using fuel with
the recommended octane rating, contact
an authorized dealer to prevent any engine
damage.
We recommend Top Tier detergent
gasolines, where available to help minimize
engine deposits and maintain optimal
vehicle and engine performance. For
additional information, refer to
www.toptiergas.com.
Note:
Use of any fuel for which the vehicle
was not designed can impair the emission
control system, cause loss of vehicle
performance, and cause damage to the
engine which may not be covered by the
vehicle Warranty.
Do not use:
• Diesel fuel.
• Fuels containing kerosene or paraffin.
• Fuel containing more than 15% ethanol
or E85 fuel.
• Fuels containing methanol.
• Fuels containing metallic-based
additives, including manganese-based
compounds.
• Fuels containing the octane booster
additive, methylcyclopentadienyl
manganese tricarbonyl (MMT).
• Leaded fuel, using leaded fuel is
prohibited by law.
The use of fuels with metallic compounds
such as methylcyclopentadienyl
manganese tricarbonyl (commonly known
as MMT), which is a manganese-based
fuel additive, will impair engine
performance and affect the emission
control system.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Fuel and RefuelingE161513

FUEL QUALITY - DIESEL
Fuel Requirements - Choosing The
Right Fuel: Vehicles Operated
Where Ultra Low Sulfur Diesel Fuel
Is Required (United
States/Canada/Puerto Rico/U.S.
Virgin Islands And Other Locales)
Note:
Your warranty will not cover damage
caused by using an improper type of fuel or
fuel additive.
Note: 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.
We recommend Top Tier diesel fuel where
available to help minimize engine deposits
and maintain optimal vehicle and engine
performance. For additional information,
refer to www.toptiergas.com.
You should use Ultra-Low Sulfur Diesel
fuel (also known as ULSD) designated as
number 1-D or 2-D with a maximum of
15-ppm sulfur in your diesel vehicle. You
may operate your vehicle on diesel fuels
containing up to 20% biodiesel, also
known as B20. These fuels should meet
the ASTM D975 diesel or the ASTM D7467
B6-B20 biodiesel industry specifications.
Outside of North America, use fuels
meeting EN590 or equivalent local market
standard. Using low sulfur diesel fuel
(16-500 ppm) or high sulfur
diesel fuel (greater than 500
ppm) in your diesel engine will cause
certain emission components to
malfunction which may also cause the
service engine soon light to illuminate
indicating an emissions-related concern. Diesel fuel is adjusted seasonally for cold
temperature. For best results at
temperatures below 19°F (-7°C), we
recommended using a diesel fuel which
has been seasonally adjusted for the
ambient conditions.
Fuel Requirements - Choosing The
Right Fuel: Vehicles Operated
Where Ultra Low Sulfur Diesel Fuel
Is Not Required
For the engine to operate reliably on
low-sulfur or high-sulfur diesel fuel, the
engine must be a factory built high-sulfur
engine (available as a dealer order option
for select markets) or an ultra low sulfur
diesel fuel configured engine that has been
retrofitted for high-sulfur diesel fuel using
Ford Motor Company dealer service parts.
Failure to use retrofit components other
than those available through your
authorized dealer will result in coolant
system damage, engine overheating,
selective catalyst reduction system or
diesel particulate filter damage and
possible base engine damage.
Use only a diesel engine configured for use
with high sulfur diesel fuel in markets with
diesel fuel that has sulfur content greater
than 15 ppm. Using low sulfur diesel fuel
(16–500 ppm) or high sulfur diesel fuel
(greater than 500 ppm) in a diesel engine
designed to use only Ultra Low Sulfur
Diesel fuel may result in damage to engine
emission control devices and the
aftertreatment system, potentially
rendering the vehicle inoperable.
Vehicles with engines configured for use
with high sulfur diesel fuel are only
available for sale in countries where ultra
low sulfur diesel fuel is generally not
available or mandated by the government.
Vehicles originally sold in a ultra low sulfur
diesel fuel market that are subsequently
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Fuel and Refueling

WARNING: Stop refueling after the
fuel pump nozzle automatically shuts
off for the second time. Failure to follow
this will fill the expansion space in the
fuel tank and could lead to fuel
overflowing. WARNING: Do not remove the fuel
pump nozzle from its fully inserted
position when refueling.
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 WARNING: The fuel system may
be under pressure. If you hear a hissing
sound near the fuel filler inlet, do not
refuel until the sound stops. Otherwise,
fuel may spray out, which could cause
serious personal injury.
Note: If you must replace the fuel filler cap,
replace it with a fuel filler cap designed for
your vehicle. The vehicle warranty may be
void for any damage to the fuel tank or fuel
system if you do not use the correct genuine
Ford or Motorcraft® fuel filler cap.
When fueling your vehicle:
1. Put your vehicle in park (P).
2. Switch the engine off. 3. Carefully turn the filler cap
counterclockwise until it spins off.
4. Pull to remove the cap from the fuel filler pipe.
5. To install the cap, align the tabs on the
cap with the notches on the filler pipe.
6. Turn the filler cap clockwise until it clicks at least once.
If the Check Fuel Cap light or a Check Fuel
Cap message appears in the instrument
cluster and stays on after you start the
engine, you may not have installed the fuel
filler properly.
If the fuel cap light remains on, at the next
opportunity, safely pull off of the road,
remove the fuel filler cap, align the cap
properly and reinstall it. The check fuel cap
light or Check fuel cap message may not
reset immediately. It may take several
driving cycles for the indicators to turn off.
A driving cycle consists of an engine
start-up, after four or more hours with the
engine off, followed by normal city and
highway driving.
REFUELING - DIESEL WARNING: Read and follow all the
instructions on the pump island. WARNING:
Stay outside your
vehicle and do not leave the fuel pump
unattended when refueling your vehicle. WARNING:
Keep children away
from the fuel pump. Never let children
pump fuel. WARNING:
Wait at least five
seconds before removing the fuel pump
nozzle to allow any residual fuel to drain
into the fuel tank.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Fuel and Refueling

FUEL CONSUMPTION
Advertised Capacity
The advertised capacity is the maximum
amount of fuel that you can add to the fuel
tank after running out of fuel. Included in
the advertised capacity is an empty
reserve. The empty reserve is an
unspecified amount of fuel that remains
in the fuel tank when the fuel gauge
indicates empty.
Note:
The amount of fuel in the empty
reserve varies and should not be relied upon
to increase driving range.
Fuel Economy
Your vehicle calculates fuel economy
figures through the trip computer average
fuel function. See General Information
(page 110).
The first
1,000 mi (1,500 km) of driving is
the break-in period of the engine. A more
accurate measurement is obtained after
2,000 mi (3,000 km)
.
Impacting Fuel Economy
• Incorrect tire inflation pressures.
• Fully loading your vehicle.
• Carrying unnecessary weight.
• Adding certain accessories to your
vehicle such as bug deflectors, rollbars
or light bars, running boards and ski
racks.
• Using fuel blended with alcohol. See
Fuel Quality
(page 185).
• Fuel economy may decrease with lower
temperatures.
• Fuel economy may decrease when
driving short distances.
• You may get better fuel economy when
driving on flat terrain than when driving
on hilly terrain.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Fuel and Refueling

EMISSION LAW
WARNING: Do not remove or alter
the original equipment floor covering or
insulation between it and the metal floor
of the vehicle. The floor covering and
insulation protect occupants of the
vehicle from the engine and exhaust
system heat and noise. On vehicles with
no original equipment floor covering
insulation, do not carry passengers in a
manner that permits prolonged skin
contact with the metal floor. Failure to
follow these instructions may result in
fire or personal injury.
U.S. federal laws and certain state laws
prohibit removing or rendering inoperative
emission control system components.
Similar federal or provincial laws may
apply in Canada. We do not approve of any
vehicle modification without first
determining applicable laws. Tampering with emissions
control systems including
related sensors or the Diesel
Exhaust Fluid system can result in reduced
engine power and the illumination of the
service engine soon light. Tampering With a Noise Control
System
Federal laws prohibit the following acts:
•
Removal or rendering inoperative by
any person other than for purposes of
maintenance.
• Repair or replacement of any device or
element of the design incorporated into
a new vehicle for the purpose of noise
control prior to its sale or delivery to
the ultimate purchaser or while it is in
use.
• The use of the vehicle after any person
removes or renders inoperative any
device or element of the design.
The U.S. Environmental Protection Agency
may presume to constitute tampering as
follows:
• Removal of hood blanket, fender apron
absorbers, fender apron barriers,
underbody noise shields or acoustically
absorptive material.
• Tampering or rendering inoperative the
engine speed governor, to allow engine
speed to exceed manufacturer
specifications.
If the engine does not start, runs rough,
experiences a decrease in engine
performance, experiences excess fuel
consumption or produces excessive
exhaust smoke, check for the following:
• A plugged or disconnected air inlet
system hose.
• A plugged engine air filter element.
• Water in the fuel filter and water
separator.
• A clogged fuel filter.
• Contaminated fuel.
• Air in the fuel system, due to loose
connections.
• An open or pinched sensor hose.
• Incorrect engine oil level.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Engine Emission Control