2011 FORD F550 4WD

If any steering components are serviced or replaced, install new
fasteners (many are coated with thread adhesive or have prevailing
torque features which may not be re-used). Never re-use a bolt or nut.
Torque fasteners to specifications in Workshop Manual .
A high crown in the road or high crosswinds may also make the steering
seem to wander/pull.
ELECTRONIC LOCKING DIFFERENTIAL (ELD) (IF EQUIPPED)
The electronic locking differential (ELD) is a device housed in the rear
axle which allows both rear wheels to turn at the same speed. It provides
added traction on slippery and/or off road surfaces, particularly when
one wheel is on a poor traction surface. The ELD may be locked or
unlocked by the vehicle operator and can be engaged or disengaged on
the fly. When the axle is unlocked it will function like a standard rear
axle. When the axle is locked it will not allow the rear wheels to rotate
at different speeds when turning. It is not recommended for use on good
traction surfaces such as dry pavement. Doing so may result in abnormal
driving behavior and noise while cornering and excessive tire wear.
The ELD is affected by the following conditions of your vehicle:
• On 2WD vehicles and 4WD vehicles in 2H (4X2) or 4H (4X4 High),
the ELD will not engage if the vehicle speed is above 25 mph
(40 km/h).
• On 2WD vehicles and 4WD vehicles in 2H (4X2) or 4H (4X4 High),
the ELD will automatically disengage at speeds above 25 mph
(40 km/h) and will automatically reengage at speeds below 19 mph
(30 km/h).
• On 4WD vehicles in 4L (4X4 Low), the ELD can be engaged at any
speed and will not automatically disengage.
Activating the electronic locking differential (ELD)
For vehicles equipped with an
electronic shift 4WD system:
Pull the knob on the 4WD control
toward you. The
indicator light
will display in the instrument
cluster.Driving
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For 2WD vehicles and vehicles
equipped with a manual shift
4WD system:
Turn the control to ON. The
indicator light will display in the
instrument cluster.
Once the light is displayed in the instrument cluster, both rear wheel
axle shafts will be locked together providing added traction.
If the
indicator light in the instrument cluster turns off, one of the
following has occurred:
• The vehicle speed is too high.
• The left and right rear wheel speed difference is too high during an
engagement attempt.
• The system has malfunctioned and will be accompanied by the
CHECK LOCKING DIFFERENTIAL message in the message center.
See your authorized Ford dealer for assistance.
Note: The ELD may have difficulty disengaging either by operator
command or automatically if the driveline is under torque. If driving
conditions allow, releasing the accelerator pedal or turning the steering
wheel in the opposite direction may assist in disengagement.
Note: The ELD is designed for off-road use only and is not intended for
use on dry pavement.
PREPARING TO DRIVE
WARNING: Utility vehicles have a significantly higher rollover
rate than other types of vehicles.
WARNING: In a rollover crash, an unbelted person is
significantly more likely to die than a person wearing a seat belt.
Utility vehicles and trucks have larger tires and increased ground
clearance, giving the vehicle a higher center of gravity than a passenger
car. Driving
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WARNING: The camera system is a reverse aid supplement
device that still requires the driver to use it in conjunction with
the rear view mirror and the side mirrors for maximum coverage.
WARNING: Objects that are close to either corner of the
bumper or under the bumper, might not be seen on the screen
due to the limited coverage of the camera system.
WARNING: Back up as slow as possible since higher speeds
might limit your reaction time to stop the vehicle.
WARNING: Do not use the camera system with the tailgate
open.
If the back end of the vehicle is hit or damaged, then check with your
authorized dealer to have your rearview camera system checked for
proper coverage and operation.
Night time and dark area use
At night time or in dark areas, the camera system relies on the reverse
lamp lighting to produce an image. Therefore it is necessary that both
reverse lamps are operating in order to get a clear image in the dark. If
either of the lamps are not operating, stop using the camera system, at
least in the dark, until the lamp(s) are replaced and functioning.
Servicing
• If the image comes on while the vehicle is not in R (Reverse), have
the system inspected by your authorized dealer.
• If the image is not clear, then check if there is anything covering the
lens such as dirt, mud, ice, snow, etc. If the image is still not clear
after cleaning, have your system inspected by your authorized dealer.
FOUR-WHEEL DRIVE (4WD) OPERATION (IF EQUIPPED)
WARNING: For important information regarding safe operation
of this type of vehicle, see Preparing to drive your vehicle in
this chapter.
When four–wheel drive (4WD) is engaged, power is supplied to all four
wheels through a transfer case. 4WD can be selected when additional
driving power is desired.Driving
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4WD operation is not recommended on dry pavement. Doing so could
result in difficult disengagement of the transfer case, increased tire wear
and decreased fuel economy.
Manual Shift On Stop (MSOS) 4x4 system (if equipped)
The 4WD system is engaged or
disengaged by rotating the control
for both front wheel hub locks from
the FREE or LOCK position, then
manually engaging or disengaging
the transfer case with the
floor-mounted shifter. For increased
fuel economy in 2WD, rotate both
hub locks to the FREE position.
• For proper operation, make
sure that each hub is fully
engaged and that both hub locks are set to the same position
(both set to LOCK or both set to FREE). To engage LOCK,
turn the hub locks completely clockwise; to disengage the hubs
(FREE), turn the hub locks completely counterclockwise.
• The vehicle should not be driven in 4X4 High or 4X4 Low
modes with the hub locks set to FREE as this condition may
damage driveline system components.
• Some vehicles may be equipped with wheel ornaments that cover the
4x4 manual hub lock. These ornaments must be removed to access
the manual hub locks.
Electronic Shift On the Fly (ESOF) 4x4 system (if equipped)
If equipped with the electronic shift 4WD system, and 4X4 Low is
selected while the vehicle is moving above 3 mph (5 km/h), the
4WD system will not perform a shift. This is normal and should be
no reason for concern. Refer to Shifting to/from 4L (4X4 Low) for
proper system operation.
The ESOF 4WD system:
• provides 4x4 High engagement and disengagement while the vehicle is
moving.
• is operated by a rotary control located on the instrument panel that
allows you select 4x2, 4x4 High or 4x4 Low operation.
• uses auto-manual hub locks that can be engaged and disengaged
automatically based on the 4x4 mode selected. Driving
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• auto-manual hub locks can be
manually overridden by rotating
the hub lock control from AUTO
to LOCK if desired.
• automatic operation of the
hub locks is recommended, and
will increase fuel economy
• For proper operation, make
sure that each hub is fully
engaged and that both hub
locks are set to the same position (both set to LOCK or both
set to AUTO). To engage LOCK, turn the hub locks completely
clockwise; to engage AUTO, turn the hub locks completely
counterclockwise.
4WD system indicator lights
The indicator lights illuminate in the message center in the
reconfigurable telltale (RTT) under the following conditions. Refer to
Warning lights and chimes in the Instrument Cluster chapter.
• 4X2 - Momentarily illuminates
when 2H is selected on electronic
shift 4WD systems only.
• 4X4 HIGH - Illuminates when 4H
(4x4 High) is engaged.
• 4X4 LOW - Illuminates when 4L
(4x4 Low) is engaged.
• CHECK 4X4 – Displays when a
4x4 system fault is present
Using a Manual Shift On Stop (MSOS) 4x4 system (if equipped)
Note: High shift efforts may be encountered when attempting to
shift into and out of 4x4 modes. It is recommended to allow the
vehicle to roll at a speed below 3 mph (5 km/h) when shifting
between modes.
Note: Some noise may be heard as the 4x4 system shifts or engages.
This is normal. In order to reduce engagement noise, it is recommended
that all shifts be performed at speeds below 3 mph (5 km/h). 4x2
4x4
HIGH
4x4
LOWDriving
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3. Move the transfer case shift lever
through N (Neutral) directly to 4H
(4x4 High) or 2H (2WD).
4. If the transfer case will not
engage into 4H (4x4 High) or 2H
(2WD), perform a shift with the
transmission in N (Neutral) and the
vehicle rolling at a speed below
3 mph (5 km/h).
5. If shifting to 2H (2WD) with the vehicle at a complete stop, disengage
the locking hubs (optional) by rotating the hub lock control from LOCK
to FREE.
Using the N (Neutral) position
The transfer case neutral
position overrides the
transmission and puts the
vehicle in neutral regardless of
transmission gearshift lever
position. The vehicle can move
forward or backwards.
This position should only be used
when towing the vehicle.
WARNING: Do not leave the vehicle unattended with the
transfer case in the N (Neutral) position. Always set the parking
brake fully and turn off the ignition when leaving the vehicle.
Using the electronic shift 4WD system (if equipped)
2H (2WD) - For general on-road
driving. Sends power to the rear
wheels only and should be used for
street and highway driving. Provides
optimal smoothness and fuel
economy at high speeds.
4H (4X4 High) - Used for extra
traction such as in snow or icy roads or in off road situations. This
mode is not intended for use on dry pavement. 2H
4H
4L N
2H
4H
4L NDriving
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4L (4X4 Low) - Uses extra gearing to provide maximum power to all
four wheels at reduced speeds. Intended only for off-road applications
such as deep sand, steep grades or pulling heavy objects. 4L (4X4 low)
will not engage while the vehicle is moving above 3 mph (5 km/h); this is
normal and should be no reason for concern. Refer to Shifting to/from
4L (4X4 low) for proper operation.
Shifting between 2H (4X2) and 4H (4X4 high)
Move the 4WD control between 2H (4X2) and 4H (4X4 high) at any
forward speed. The message center will display 4X4 SHIFT IN
PROGRESS during the system shift. “4X4 HIGH” will display in the
message center if 4H is selected and “4X2” will momentarily display in
the message center if 2H is selected.
If SHIFT DELAYED PULL FORWARD is displayed in the message
center during the mode shift, transfer case gear tooth blockage is
present. To alleviate this condition, place the transmission in a forward
gear and move the vehicle forward approximately 5 feet (2 meters) to
allow the transfer case to complete the mode shift.
Note: Momentarily releasing the accelerator pedal while performing a
shift will improve engagement/disengagement times.
Note: Do not perform this operation if the rear wheels are slipping.
Note: Some noise may be heard as the system shifts or engages; this is
normal.
Note: 4X4 high mode is not intended for use on dry pavement.
Shifting to/from 4L (4X4 low)
1. Bring the vehicle to a speed of 3 mph (5 km/h) or less.
2. Place the transmission in N (Neutral).
3. Move the 4WD control to the desired position.
The message center will display 4X4 SHIFT IN PROGRESS during the
shift. The message center will then display the system mode selected. If
any of the above shift conditions are not met, the shift will not occur and
the message center will display information guiding the driver through
the proper shifting procedures.
If SHIFT DELAYED PULL FORWARD is displayed in the message
center, transfer case gear tooth blockage is present. To alleviate this
condition, place the transmission in a forward gear, move the vehicle
forward approximately 5 feet (1.5 m), and shift the transmission back to
neutral to allow the transfer case to complete the range shift.Driving
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Note: Some noise may be heard as the system shifts or engages; this is
normal.
Note: 4x4 low mode is not intended for use on dry pavement.
Driving off-road with truck and utility vehicles
4WD 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.
Your vehicle may be equipped with a long front air dam that may become
damaged (due to reduced ground clearance) when taking your vehicle
off-road. This air dam can either be removed or a shorter air dam can be
purchased from your authorized dealer. In either case, if the air dam is
to be removed (or replaced) before going off-road, refer to the
Workshop Manual for the procedure or have your authorized dealer
perform the work for you.
How your vehicle differs from other vehicles
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.
Basic operating principles
• Do not use 4WD on dry, hard surfaced roads. Doing so will produce
excessive noise, increase tire wear and may damage drive components.
4WD modes are only intended for consistently slippery or loose
surfaces.
• Drive slower in strong crosswinds which can affect the normal steering
characteristics of your vehicle. Driving
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