2021 FORD F-350 suspension

Maintenance and Modifications
The suspension and steering systems on
your vehicle have been designed and
tested to provide predictable performance
whether loaded or empty. For this reason,
we strongly recommend that you do not
make modifications such as adding or
removing parts (i.e. lift kits or stabilizer
bars) or by using replacement parts not
equivalent to the original factory
equipment.
We recommend that you use caution when
your vehicle has either a high load or device
(i.e. ladder or luggage racks). Any
modifications to your vehicle that raise the
center of gravity may cause your vehicle
to roll over when there is a loss of vehicle
control.
Failure to maintain your vehicle correctly
may void the warranty, increase your repair
cost, reduce vehicle performance and
operational capabilities and adversely
affect you and your passenger's safety. We
recommend you frequently inspect your
vehicle's chassis components when your
vehicle is subject to off road usage.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Four-Wheel Drive (If Equipped)

PRINCIPLE OF OPERATION
WARNING: Vehicle modifications
involving braking system, aftermarket
roof racks, suspension, steering system,
tire construction and wheel and tire size
may change the handling characteristics
of your vehicle and may adversely affect
the performance of the electronic
stability control system. In addition,
installing any stereo loudspeakers may
interfere with and adversely affect the
electronic stability control system. Install
any aftermarket stereo loudspeaker as
far as possible from the front center
console, the tunnel, and the front seats
in order to minimize the risk of interfering
with the electronic stability control
sensors. Reducing the effectiveness of
the electronic stability control system
could lead to an increased risk of loss of
vehicle control, vehicle rollover, personal
injury and death. WARNING:
Remember that even
advanced technology cannot defy the
laws of physics. It’ s always possible to
lose control of a vehicle due to
inappropriate driver input for the
conditions. Aggressive driving on any
road condition can cause you to lose
control of your vehicle increasing the risk
of personal injury or property damage.
Activation of the electronic stability
control system is an indication that at
least some of the tires have exceeded
their ability to grip the road; this could
reduce the operator ’s ability to control
the vehicle potentially resulting in a loss
of vehicle control, vehicle rollover,
personal injury and death. If your
electronic stability control system
activates, SLOW DOWN.
The system automatically turns on each
time you switch the ignition on. If a fault occurs in either the stability
control or the traction control system, you
may experience the following conditions:
•
The stability and traction control light
illuminates steadily.
• The stability control and traction
control systems do not enhance your
vehicle's ability to maintain traction of
the wheels.
• The Adaptive Steering system (if
equipped) automatically changes the
steering function to a fixed steering
ratio. See
Adjusting the Steering
Wheel (page 81).
If a driving condition activates either the
stability control or the traction control
system you may experience the following
conditions:
• The stability and traction control light
flashes.
• Your vehicle slows down.
• Reduced engine power.
• A vibration in the brake pedal.
• The brake pedal is stiffer than usual.
• If the driving condition is severe and
your foot is not on the brake, the brake
pedal may move as the system applies
higher brake force.
The stability control system has several
features built into it to help you maintain
control of your vehicle:
Electronic Stability Control
The system enhances your vehicle ’s ability
to prevent skids or lateral slides by
applying brakes to one or more of the
wheels individually and, if necessary,
reducing engine power.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Stability Control

DRIVER ALERT (IF EQUIPPED)
WARNING: You are responsible for
controlling your vehicle at all times. The
system is designed to be an aid and does
not relieve you of your responsibility to
drive with due care and attention. Failure
to follow this instruction could result in
the loss of control of your vehicle,
personal injury or death. WARNING:
The system may not
function if the sensor is blocked. WARNING:
Take regular rest
breaks if you feel tired. Do not wait for
the system to warn you. WARNING:
Certain driving styles
may result in the system warning you
even if you are not feeling tired. WARNING:
In cold and severe
weather conditions the system may not
function. Rain, snow and spray can all
limit sensor performance. WARNING:
The system will not
operate if the sensor cannot track the
road lane markings. WARNING:
If damage occurs in the
immediate area surrounding the sensor,
have your vehicle checked as soon as
possible. WARNING:
The system may not
correctly operate if your vehicle is fitted
with a suspension kit not approved by
us.
Note: Keep the windshield free from
obstructions. For example, bird droppings,
insects and snow or ice. Note:
If you have a blocked camera or
damaged windshield, the system may not
function.
Note: The system remembers the last
setting when you start your vehicle, unless
it detects a MyKey ™.
Note: If enabled in the menu, the system
activates at speeds above
40 mph
(64 km/h). The system monitors your driving behavior
using various inputs including the front
camera sensor.
If the system detects reduced driving
alertness below a certain threshold, the
system alerts you using a tone and a
message in the information display.
Using Driver Alert
Switching the system on and off
You may switch the system on or off
through the information display by
selecting Settings, Driver Assist and then
Driver Alert in the menu. When activated,
the system monitors your alertness level
based upon your driving behavior in relation
to the lane markings, and other factors.
System Warnings
Note:
The system does not issue warnings
below approximately
40 mph (64 km/h).
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Driving AidsE249505

The warning system is in two stages. At
first the system issues a temporary warning
that you need to take a rest. This message
only appears for a short time. If the system
detects further reduction in driving
alertness, another warning could be issued
which remains in the information display
for a longer time. Press OK on the steering
wheel control to clear the warning. When
active the system runs in the background
and only issues a warning if required.
Resetting the System
You can reset the system by either:
•
Switching the ignition off and on.
• Stopping the vehicle and then opening
and closing the driver door.
LANE KEEPING SYSTEM (IF
EQUIPPED) WARNING: You are responsible for
controlling your vehicle at all times. The
system is designed to be an aid and does
not relieve you of your responsibility to
drive with due care and attention. Failure
to follow this instruction could result in
the loss of control of your vehicle,
personal injury or death. WARNING:
Always drive with due
care and attention when using and
operating the controls and features on
your vehicle. WARNING:
In cold and severe
weather conditions the system may not
function. Rain, snow and spray can all
limit sensor performance. WARNING:
The system will not
operate if the sensor cannot track the
road lane markings. WARNING:
The sensor may
incorrectly track lane markings as other
structures or objects. This can result in
a false or missed warning. WARNING:
Large contrasts in
outside lighting can limit sensor
performance. WARNING:
The system may not
operate properly if the sensor is blocked.
Keep the windshield free from
obstruction. WARNING:
If damage occurs in the
immediate area surrounding the sensor,
have your vehicle checked as soon as
possible. WARNING:
The system may not
correctly operate if your vehicle is fitted
with a suspension kit not approved by
us.
Note: The system works as long as the
camera can detect one lane marking at a
speed above
40 mph (64 km/h).
Note: The system may not function with a
blocked camera, or if the windshield is
damaged or dirty. 251
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Driving AidsE249505

STEERING
Hydraulic Power Steering
To help prevent damage to the power
steering system:
•
Do not hold the steering wheel at its
furthest turning points for more than
three to five seconds when the engine
is running.
• Avoid continuously steering back and
forth with elevated engine RPM as this
may overheat the system. If trying to
free a stuck vehicle, pause between
attempts to allow the power steering
system to cool or seek assistance.
Typical steering and driving maneuvers
allow the system to cool.
• Do not operate the vehicle if the power
steering pump fluid level is below the
MIN mark on the reservoir.
• Some noise is normal during operation.
If excessive, check for low power
steering pump fluid level before
seeking service by your dealer.
• Heavy or uneven efforts may be caused
by low power steering fluid. Check for
low power steering pump fluid level
before seeking service by your dealer.
• Do not fill the power steering pump
reservoir above the MAX mark on the
reservoir, as this may result in leaks
from the reservoir.
If the power steering system breaks down
or if you switch the engine off, you can
steer the vehicle manually, but it takes
more effort.
If you have any steering components
serviced or replaced, install new fasteners.
Many fasteners have coatings with thread
adhesive, or have prevailing torque
features you cannot reuse. Do not reuse a
bolt or nut. Torque fasteners to
specifications. Steering Tips
If the steering wanders or pulls, check for:
•
An improperly inflated tire.
• Uneven tire wear.
• Loose or worn suspension
components.
• Loose or worn steering components.
• Improper vehicle alignment.
Note: A high crown in the road or high
crosswinds may also make the steering
seem to wander or pull.
Electronic Torque Overlay Steering
(If Equipped) WARNING: The electric power
steering system has diagnostic checks
that continuously monitor the system. If
a fault is detected, a message displays
in the information display. Stop your
vehicle as soon as it is safe to do so.
Switch the ignition off. After at least 10
seconds, switch the ignition on and
watch the information display for a
steering system warning message. If a
steering system warning message
returns, have the system checked as
soon as possible. WARNING:
If the system detects
an error, you may not feel a difference in
the steering, however a serious condition
may exist. Have your vehicle checked as
soon as possible. Failure to do so may
result in loss of steering control.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Driving Aids

TOWING A TRAILER
WARNING: Do not exceed
the GVWR or the GAWR
specified on the certification
label. WARNING:
Towing trailers
beyond the maximum
recommended gross trailer
weight exceeds the limit of your
vehicle and could result in engine
damage, transmission damage,
structural damage, loss of
vehicle control, vehicle rollover
and personal injury. WARNING:
Do not exceed
the lowest rating capacity for
your vehicle or trailer hitch.
Overloading your vehicle or
trailer hitch can impair your
vehicle stability and handling.
Failure to follow this instruction
could result in the loss of control
of your vehicle, personal injury or
death. WARNING:
Do not cut,
drill, weld or modify the trailer
hitch. Modifying the trailer hitch
could reduce the hitch rating.
Your vehicle may have electrical
items, such as fuses or relays,
related to towing. See
Fuse
Specification Chart (page 339). Your vehicle may have ability to
modify trailer towing features.
See
General Information (page
110).
Your vehicle's load capacity
designation is by weight, not by
volume, so you cannot necessarily
use all available space when
loading a vehicle or trailer.
Towing a trailer places an extra
load on your vehicle's engine,
transmission, axle, brakes, tires
and suspension. Inspect these
components periodically during,
and after, any towing operation.
Note: To prevent your trailer from
accumulating distance, and the
trailer information status appearing
when you restart your vehicle after
disconnecting your trailer, you must
deactivate your trailer. Using the
information display, go to the
Towing menu and then the Select
Trailer option. Select the No active
trailer option. See
General
Information (page 110).
Load Placement
To help minimize how trailer
movement affects your vehicle
when driving:
• Load the heaviest items closest
to the trailer floor.
• Load the heaviest items
centered between the
left-hand and right-hand side
trailer tires.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Towing

•
Placing the sticker on a surface angled
away from the vehicle reduces
performance. Use a drawbar that
positions the trailer level to the ground
when attached to the vehicle. This
typically provides a level surface to
mount the sticker. Place the sticker on
a bracket or other object when no level
surface is available.
• Make sure the entire sticker is on a flat
surface that is completely visible to the
camera. Do not fold the sticker over an
edge on the trailer frame. This can
degrade performance.
• Shadows on the sticker may affect
tracking performance under some
lighting conditions. Moving the sticker
to another location within the allowed
placement area may improve
performance. Use the change sticker
option in the information display menu
if you move the sticker.
• You can change your sticker location
by going into the information display
menu, selecting trailer options,
selecting change trailer settings and
then selecting the change sticker
option. The previous sticker must be
removed. ONLY ONE STICKER
SHOULD BE PLACED ON THE TRAILER
FOR CORRECT SYSTEM FUNCTION. •
The camera system uses the entered
measurements to help locate the
sticker. Inaccurate measurements
reduce the system ’s ability to locate
the sticker. Check the measurements
entered into the system are correct.
Refer to step 4 of setup for instructions
on measurements.
• You can change your measurement by
going into the information display
menu, selecting trailer options,
selecting change trailer setting and
then selecting the change sticker
option. Disregard the prompt to remove
this sticker and continue to the next
step if you only plan to update the
measurements for the current sticker
location.
System does not reverse straight:
• Factors such as the drawbar
connection to the hitch receiver, road
camber, road grade and compliance in
the trailer suspension can influence
how straight the system is able to
reverse your trailer when the knob is
not turned. You can compensate for
the trailer drifting to the right or left by
slowly turning the knob until the trailer
is following your preferred path and
then holding the knob in that position.
If you would like to recalibrate the
system for straight backing, you can do
so with the following procedure.
• Go into the information display menu,
select trailer options, select change
trailer setting and then select the
change sticker option. Your saved
measurements display. Do not change
them but continue to confirm
measurements. Once you confirm the
measurements, the system then
prompts you to perform the calibration
procedure.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Towing

Pro Trailer Backup Assist™ Trailer Not
Detected Pull Forward to Initialize Press
Knob to Exit or Trailer Reverse Guidance
Trailer Not Detected Pull Forward to
Initialize Press OK to Exit:
•
If the vehicle has not moved during this
key cycle, it must be driven forward to
initialize the sensing system.
• Extended operation at speeds below
1 mph (1 km/h) may cause the sensing
system to lose the trailer position and
the system needs to be re-initialized.
• Drive forward above 2 mph (3 km/h)
and the system indicates when it
initializes.
System repeatedly displays Pro Trailer
Backup Assist™ Stop Now System Not
Active Press Knob to Exit:
• System is not fully activated. Select
the trailer in the information display by
using the controls on the steering
wheel and wait until Pro Trailer Backup
Assist™ Backup Slowly Turn Knob to
Steer Press Knob to Exit displays
before starting to move backward.
• This displays if you backup during the
calibration process. Drive forward and
complete calibration.
System does not reverse straight:
• Verify sensor is correctly installed. See
Fifth Wheel and Gooseneck Trailer
Sensor Installation.
• Factors such as the hitch connection,
road camber, road slope and
compliance in the trailer suspension
can influence how straight the system
is able to reverse the trailer when the
knob is not turned. You can
compensate for the trailer drifting to
the right or left by slowly turning the
knob until the trailer is following your
preferred path and then holding the
knob in that position. System consistently shows Pro Trailer
Backup Assist™ Stop now Maximum trailer
angle Press Knob to Exit:
•
Verify sensor is correctly installed. See
Fifth Wheel and Gooseneck Trailer
Sensor Installation.
• Verify the correct trailer is selected in
the information display.
• The system may need to be
recalibrated. The system can be
recalibrated by using the information
display to delete the trailer and
repeating the setup process. If the
same sensor is installed on another
trailer, create a new trailer in the
information display and complete the
setup and calibration process for the
new trailer. If using the same sensor on
multiple trailers, disconnect the 7/12
pin connector when switching trailers.
See Setting Up The System.
System consistently shows Pro Trailer
Backup Assist™ Stop Now Take Control
of Steering Wheel:
• The system displays this warning when
it can no longer steer the vehicle and
you must take over steering. There are
four reasons why this warning displays
and additional information regarding
the reason for the warning is available
on the center display.
• The steering wheel is touched when
under system control. Avoid touching
the wheel during system operation.
• The maximum speed for feature
operation is exceeded. System
performance is optimized at slower
speeds. Reverse slowly.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Towing