2021 FORD SUPER DUTY ECO mode

How Your Vehicle Differs from
Other Vehicles
WARNING: Vehicles with a higher
center of gravity (utility and four-wheel
drive vehicles) handle differently than
vehicles with a lower center of gravity
(passenger cars). Avoid sharp turns,
excessive speed and abrupt steering in
these vehicles. Failure to drive cautiously
increases the risk of losing control of your
vehicle, vehicle rollover, personal injury
and death.
Truck and utility vehicles can differ from
some other vehicles. Your vehicle may be
higher to allow it to travel over rough
terrain without getting hung up or
damaging underbody components.
The differences that make your vehicle so
versatile also make it handle differently
than an ordinary passenger car.
Maintain steering wheel control at all
times, especially in rough terrain. Since
sudden changes in terrain can result in
abrupt steering wheel motion, make sure
you grip the steering wheel from the
outside. Do not grip the spokes.
Drive cautiously to avoid vehicle damage
from concealed objects such as rocks and
stumps.
You should either know the terrain or
examine maps of the area before driving.
Map out your route before driving in the
area. To maintain steering and braking
control of your vehicle, you must have all
four wheels on the ground and they must
be rolling, not sliding or spinning. Driving Off-Road With Truck and
Utility Vehicles
Note:
On some models, the initial shift from
two-wheel drive to four-wheel drive while
the vehicle is moving can cause some
momentary clunk and ratcheting sounds.
This is the front drivetrain coming up to
speed and the automatic locking hubs
engaging and is not cause for concern.
Note: Your vehicle may come with a front
air dam that can become damaged (due to
reduced ground clearance) when taking your
vehicle off-road. This air dam can be taken
off by removing 15 bolts.
Four-wheel drive vehicles are specially
equipped for driving on sand, snow, mud
and rough terrain and have operating
characteristics that are somewhat
different from conventional vehicles, both
on and off the road.
Power is supplied to all four wheels
through a transfer case. On four-wheel
drive vehicles, the transfer case allows you
to select 4WD when necessary.
Information on transfer case operation and
shifting procedures can be found in this
chapter. Information on transfer case
maintenance can be found in the
Maintenance chapter. You should become
thoroughly familiar with this information
before you operate your vehicle.
Four-wheel drive (when you select a 4WD
mode) uses all four wheels to power the
vehicle. This increases traction, enabling
you to drive over terrain and road
conditions that a conventional two-wheel
drive vehicle cannot.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing Four-Wheel Drive
(If Equipped)

Basic Operating Principles
•
Drive slower in strong crosswinds which
can affect the normal steering
characteristics of your vehicle.
• When driving your vehicle on surfaces
made slippery by loose sand, water,
gravel, snow or ice proceed with care.
• Do not use 4H or 4L on dry, hard
surfaced roads. Doing so will produce
excessive noise, increase tire wear and
may damage drive components. 4H or
4L modes are only intended for
consistently slippery or loose surfaces.
If Your Vehicle Leaves the Road
If your vehicle leaves the road, reduce your
vehicle speed and avoid severe braking.
When your vehicle speed has been
reduced, ease your vehicle back onto the
road. Do not turn the steering wheel
sharply while returning your vehicle to the
road.
It may be safer to stay on the shoulder of
the road and slow down gradually before
returning to the road. You may lose control
if you do not slow down or if you turn the
steering wheel too sharply or abruptly.
It may be less risky to strike small objects,
such as freeway reflectors, with minor
damage to your vehicle rather than
attempt a sudden return to the road which
could cause your vehicle to slide sideways
out of control or roll over. Remember, your
safety and the safety of others should be
your primary concern.
Emergency Maneuvers
In an unavoidable emergency situation
where a sudden sharp turn must be made,
remember to avoid over-driving your
vehicle (i.e. turn the steering wheel only as
rapidly and as far as required to avoid the
emergency). Excessive steering can result
in loss of vehicle control. Apply smooth
pressure to the accelerator pedal or brake pedal when changes in vehicle speed are
required. Avoid abrupt steering,
acceleration and braking. This could result
in an increased risk of vehicle roll over, loss
of vehicle control and personal injury. Use
all available road surface to bring your
vehicle to a safe direction of travel.
In the event of an emergency stop, avoid
skidding the tires and do not attempt any
sharp steering wheel movements.
If your vehicle goes from one type of
surface to another (i.e. from concrete to
gravel) there will be a change in the way
your vehicle responds to a maneuver (i.e.
steering, acceleration or braking).
Sand
When driving over sand, try to keep all four
wheels on the most solid area of the trail.
Avoid reducing the tire pressures but shift
to a lower gear and drive steadily through
the terrain. Apply the accelerator slowly
and avoid excessive wheel slip.
When driving at slow speeds in deep sand
under high outside temperatures, use a low
gear when possible. Low gear operation
will maximize the engine and transmission
cooling capability.
Avoid driving at excessive speeds, this
causes vehicle momentum to work against
you and your vehicle could become stuck
to the point that assistance may be
required from another vehicle. Remember,
you may be able to back out the way you
came if you proceed with caution.
Mud and Water
Mud
Be cautious of sudden changes in vehicle
speed or direction when you are driving in
mud. Even four-wheel drive vehicles can
lose traction in slick mud. If your vehicle
does slide, steer in the direction of the slide
until you regain control of your vehicle.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing Four-Wheel Drive (If Equipped)

LIMITED SLIP DIFFERENTIAL
(IF EQUIPPED)
This axle provides added traction on
slippery surfaces, particularly when one
wheel is on a poor traction surface. Under
normal conditions, the limited-slip axle
functions like a standard rear axle. The axle
may exhibit a slight noise or vibration
during tight turns with low vehicle speed.
This is normal behavior and indicates the
axle is working.
ELECTRONIC LOCKING
DIFFERENTIAL (IF EQUIPPED)
Note: The electronic locking differential is
for off-road use only and is not for use on
dry pavement. Using the electronic locking
differential on dry pavement will result in
increased tire wear, noise and vibration.
The electronic locking differential is a
device housed in the rear axle that allows
both rear wheels to turn at the same
speed. The electronic locking differential
can provide additional traction should your
vehicle become stuck. You can activate
the differential electronically and shift it
on the fly within the differential operating
speed range. The differential is for use in
mud, rocks, sand, or any off-road condition
where you need maximum traction. It is
not for use on dry pavement.
The following conditions will affect the
electronic locking differential:
• The electronic locking differential will
not engage if your vehicle speed is
above 20 mph (32 km/h) in 4x2, or 4x4
High modes.
• The electronic locking differential will
not engage if your vehicle speed is
above or
56 mph (90 km/h) in 4X4
Low. •
The electronic locking differential may
not engage if you press your
accelerator pedal during an
engagement attempt. A message may
display in the instrument display
guiding you to release the accelerator
pedal.
• In 4x2, and 4x4 High modes, the
electronic locking differential will
automatically disengage at speeds
above
25 mph (41 km/h) and will
automatically reengage at speeds
below
20 mph (32 km/h).
• In 4L (4X4 low), the electronic locking
differential will automatically
disengage at speeds above
62 mph
(100 km/h) and will automatically
reengage at speeds below 56 mph
(90 km/h).
• The AdvanceTrac system has the
ability to take over control of the
electronic locking differential and
disable it during driving maneuvers
when necessary.
When you switch the system on, if you do
not meet the required conditions for
electronic locking differential activation,
the instrument cluster will display the
appropriate information guiding you
through the proper activation process.
Activating the Electronic Locking
Differential
Note: Do not use electronic locking
differential on dry, hard surfaced roads.
Doing so will produce excessive noise,
vibration and increase tire wear.
Note: If the electronic locking differential
has difficulty disengaging, release the
accelerator pedal and turn the steering
wheel in the opposite direction while rolling.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing Rear Axle

This feature increases engine braking at
higher engine speeds to provide better
grade descent control with less brake and
transmission wear and tear.
Note:
Use this when driving downhill and
carrying heavy loads or trailering.
Benefits of engine braking are:
• Lower brake temperature.
• Reduced brake fade.
• Longer brake life.
• Improved driving and trailering control. Press the button on the switch
bank next to the audio unit to
switch the system on or off.
There are two engine brake modes, manual
and automatic.
Manual Engine Braking
1. Press the button to switch on manual engine braking.
2. Release the accelerator pedal to maximize engine braking.
3. Apply the brakes. The transmission downshifts to lower gears.
Note: The engine braking feature only
functions when you release the accelerator.
Note: You can shift the transmission to
lower gears with progressive range selection
(PRS) or manual shifting independent of
pressing the brakes.
Note: You can also use manual engine
braking with cruise control to improve grade
descent control.
Note: If your vehicle has Adaptive Cruise
Control, the speed control system uses the
selected engine brake mode, transmission
gears, and brakes to maintain the set speed
and distance to the vehicle being followed. Automatic Engine Braking
1. Press the button twice to switch on
automatic engine braking.
2. Release the accelerator or brake pedal.
The system remembers your vehicle
speed.
Note: This feature offers smoother, less
aggressive engine braking during downhill
descents. It may not apply braking if the
vehicle speed is not increasing, although it
will apply full engine braking force when
needed to prevent acceleration. The system
automatically activates the engine brake
and, if necessary, downshifts the
transmission to lower gears to not exceed
your vehicle's set speed when the brake or
accelerator were last released.
Warning Lamp Conditions
• Illuminates when this feature is
switched on and the system is
operating properly. See Warning
Lamps and Indicators (page 105).
• Flashes when the engine brake is
disabled due to a fault or the engine
does not meet the required braking
conditions.
• Does not illuminate when the switch
or indicator is faulty.
You can switch the system on at anytime.
The system becomes active once the
braking conditions are met.
Braking Conditions
• Your vehicle is in a forward gear.
• The engine speed is above about 1500
RPM.
• Your foot is off the accelerator.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing BrakesE171217

PRINCIPLE OF OPERATION
The traction control system helps avoid
drive wheel spin and loss of traction.
If your vehicle begins to slide, the system
applies the brakes to individual wheels
and, when needed, reduces engine power
at the same time. If the wheels spin when
accelerating on slippery or loose surfaces,
the system reduces engine power in order
to increase traction.
USING TRACTION CONTROL
WARNING: The stability and
traction control light illuminates steadily
if the system detects a failure. Make sure
you did not manually disable the traction
control system using the information
display controls or the switch. If the
stability control and traction control light
is still illuminating steadily, have the
system serviced by an authorized dealer
immediately. Operating your vehicle with
the traction control disabled could lead
to an increased risk of loss of vehicle
control, vehicle rollover, personal injury
and death.
The system automatically turns on each
time you switch the ignition on.
If your vehicle is stuck in mud or snow,
switching traction control off may be
beneficial as this allows the wheels to spin.
Note: When you switch traction control off,
stability control remains fully active.
Note: For additional information on the
traction and stability control systems. See
Using Stability Control
(page 229). Switching the System Off
When you switch the system off or on, a
message appears in the information
display showing system status.
Use the traction and stability control
switch on the instrument panel to switch
the system off or on.
The switch illuminates when traction
control is off.
When you place your vehicle into
four-wheel drive low mode the traction
control disables. Traction control resumes
full operation when you put your vehicle
back into two-wheel drive mode.
System Indicator Lights and
Messages
The stability and traction control
light:
• Temporarily illuminates on engine
start-up.
• Flashes when a driving condition
activates either of the systems.
• Illuminates if a problem occurs in either
of the systems. The stability and traction control
off light temporarily illuminates
on engine start-up and stays on
when you switch the traction control
system off.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing Traction ControlE225465 E225466

PRINCIPLE OF OPERATION
WARNING: Hill descent control
cannot control descent in all surface
conditions and circumstances, such as
ice or extremely steep grades. Hill
descent control is a driver assist system
and cannot substitute for good judgment
by the driver. Failure to do so may result
in loss of vehicle control, crash or serious
injury. WARNING:
The system does not
replace the parking brake. When you
leave your vehicle, always apply the
parking brake and shift the transmission
into park (P) for automatic transmission
or first gear for manual transmission.
Hill descent control allows the driver to set
and maintain vehicle speed while
descending steep grades in various surface
conditions.
Hill descent control can maintain vehicle
speeds on downhill grades between 2 mph
(3 km/h)
and 12 mph (20 km/h). Above
20 mph (32 km/h), the system remains
armed, but descent speed cannot be set
or maintained.
Hill descent control requires a cooling
down interval after a period of sustained
use. The amount of time that the feature
can remain active before cooling varies
with conditions. The system will provide
a warning in the message center and a
chime will sound when the system is about
to disengage for cooling. At this time,
manually apply the brakes as needed to
maintain descent speed. USING HILL DESCENT
CONTROL Press and release the hill
descent button on the
instrument panel. A light in the
cluster illuminates and a tone sounds
when this feature is activated.
To increase descent speed, press the
accelerator pedal until the desired speed
is reached. To decrease descent speed,
press the brake pedal until the desired
speed is reached.
Whether accelerating or decelerating, once
the desired descent speed is reached,
remove your feet from the pedals and the
chosen vehicle speed is maintained.
Note: Noise from the ABS pump motor may
be observed during hill descent control
operation. This is a normal characteristic of
the ABS and should be no reason for
concern.
Hill Descent Modes
• At speeds below
20 mph (32 km/h):
When the hill descent control switch is
pressed and hill descent control is
active, the hill descent control telltale
flashes.
• At speeds below
20 mph (32 km/h):
When the hill descent control switch is
pressed and conditions are not correct
for hill descent activation, the hill
descent control system is enabled and
the hill descent control telltale is solid.
A message displays in the information
display.
• At speeds above
20 mph (32 km/h):
When the hill descent control switch is
pressed, the hill descent control
system is enabled, the telltale in the
cluster is not illuminated and a
message is displayed in the information
display.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing Terrain Control
(If Equipped)E163957

WHAT IS CRUISE CONTROL
Cruise control lets you maintain a set
speed without keeping your foot on the
accelerator pedal.
Requirements
Use cruise control when the vehicle speed
is greater than 20 mph (30 km/h).
SWITCHING CRUISE CONTROL
ON AND OFF WARNING:
Do not use cruise
control on winding roads, in heavy traffic
or when the road surface is slippery. This
could result in loss of vehicle control,
serious injury or death.
The cruise controls are on the steering
wheel. See
Switching Cruise Control
On and Off (page 242).
Switching Cruise Control On Press the button.
Switching Cruise Control Off Press the button when the
system is in standby mode.
The system also turns off when you switch
the ignition off.
Note: The set speed erases when you
switch the system off. SETTING THE CRUISE
CONTROL SPEED WARNING:
When you are going
downhill, your vehicle speed could
increase above the set speed. The
system does not apply the brakes.
Drive to the speed you prefer. Press either button to set the
current speed.
Take your foot off the accelerator pedal.
Note: The indicator changes color in the
information display.
Changing the Set Speed Press and release the button to
increase the set speed in small
increments.
Press and hold the button to accelerate.
Release the button when you reach your
preferred speed. Press and release the button to
decrease the set speed in small
increments.
Press and hold the button to decelerate.
Release the button when you reach your
preferred speed.
Note: If you accelerate by pressing the
accelerator pedal, the set speed does not
change. When you release the accelerator
pedal, your vehicle returns to the speed that
you previously set.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing Cruise Control
(If Equipped)E265296 E265297

Automatic Cancellation
The system is not functional at vehicle
speeds below 12 mph (20 km/h). The
information display indicates low engine
speed, an audible alarm sounds and the
automatic braking releases if the vehicle
drops below this speed.
Automatic cancellation can also occur
when:
•
The tires lose traction.
• You apply the parking brake.
Note: If the engine speed drops too low, an
audible warning sounds and a message
appears in the information display.
Automatic braking releases.
Hilly Condition and Trailer Tow
Usage
You should select a lower gear when the
system is active in situations such as
prolonged downhill driving on steep
grades, for example in mountainous areas.
The system needs additional engine
braking in these situations to reduce the
load on the vehicle ’s regular brake system
to prevent it from overheating.
Note: An audible alarm sounds and the
system shuts down if it applies brakes for
an extended period of time. This allows the
brakes to cool. The system functions
normally again after the brakes cool.
Note: When towing with adaptive cruise
control, switch on Tow/Haul Mode and
Diesel Engine Brake.
Note: Tow/Haul mode increases the time
gaps and allows more distance for braking.
Switching Adaptive Cruise Control
Off Press and release the button
when the system is in standby
mode, or switch the ignition off. Note:
You erase the set speed and gap
setting when you switch the system off.
Detection Issues WARNING: On rare occasions,
detection issues can occur due to the
road infrastructures, for example bridges,
tunnels and safety barriers. In these
cases, the system may brake late or
unexpectedly. At all times, you are
responsible for controlling your vehicle,
supervising the system and intervening,
if required. WARNING:
If the system
malfunctions, have your vehicle checked
as soon as possible.
The radar sensor has a limited field of view.
It may not detect vehicles at all or detect
a vehicle later than expected in some
situations. The lead vehicle graphic does
not illuminate if the system does not
detect a vehicle in front of you.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Second-Printing Cruise Control
(If Equipped)E265297