Ford F-550 (2017 year). Manual — part 54

For 4WD vehicles

E191852

Pull the 4WD control knob toward you.

For 2WD vehicles

E183740

Turn the control to ON.

E163170

Once the indicator light
illuminates in the information
display, both rear wheel axle

shafts will be locked together providing
added traction.

If the indicator does not come on, or the
indicator turns off while driving, 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 is
accompanied by CHECK LOCKING
DIFFERENTIAL in the information
display. See your authorized Ford
dealer for assistance.

GENERAL INFORMATION

Note: Occasional brake noise is normal. If
a metal-to-metal, continuous grinding or
continuous squeal sound is present, the
brake linings may be worn-out. Have the
system checked by an authorized dealer. If
your vehicle has continuous vibration or
shudder in the steering wheel while braking,
have it checked by an authorized dealer.

Note: Brake dust may accumulate on the
wheels, even under normal driving
conditions. Some dust is inevitable as the
brakes wear and does not contribute to
brake noise. See Cleaning the Wheels
(page 366).

E144522

See Warning Lamps and
Indicators (page 105).

Wet brakes result in reduced braking
efficiency. Gently press the brake pedal a
few times when driving from a car wash or
standing water to dry the brakes.

Brake Over Accelerator

In the event the accelerator pedal
becomes stuck or entrapped, apply steady
and firm pressure to the brake pedal to
slow the vehicle and reduce engine power.
If you experience this condition, apply the
brakes and bring your vehicle to a safe
stop. Move the transmission to park (P),
switch the engine off and apply the parking
brake. Inspect the accelerator pedal for
any interference. If none are found and the
condition persists, have your vehicle towed
to the nearest authorized dealer.

Brake Assist

Brake assist detects when you brake
rapidly by measuring the rate at which you
press the brake pedal. It provides
maximum braking efficiency as long as you
press the pedal, and can reduce stopping
distances in critical situations.

Anti-lock Brake System

This system helps you maintain steering
control during emergency stops by keeping
the brakes from locking.

This lamp momentarily
illuminates when you switch the
ignition on. If the light does not

illuminate during start up, remains on or
flashes, the system may be disabled. Have
the system checked by an authorized
dealer. If the anti-lock brake system is
disabled, normal braking is still effective.

E144522

If the brake warning lamp
remains illuminated after you
release the parking brake, have

the system checked by an authorized
dealer.

Diesel Engine Braking

(If Equipped)

WARNING

Do not use tow/haul or engine
braking when driving in icy or slippery
conditions as the increased braking

can cause the rear wheels to slide and your
vehicle to swing around with the possible
loss of vehicle control.

This feature increases engine braking at
higher engine speeds to provide better
grade descent control with less brake and
transmission wear and tear. It also
improves engine braking when towing or
carrying heavy loads.

E171217

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: 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.

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: 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.

Note: Use this when driving downhill and
carrying heavy loads or trailering.

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.

You can use this feature with tow/haul or
progressive range selection to provide
further increased engine braking. The
transmission automatically upshifts to
prevent the engine from entering the red
zone on the tachometer. See Automatic
Transmission (page 205).

HINTS ON DRIVING WITH
ANTI-LOCK BRAKES

Note: When the system is operating, the
brake pedal may pulse and may travel
further. Maintain pressure on the brake
pedal. You may also hear a noise from the
system. This is normal.

The anti-lock braking system will not
eliminate the risks when:
•

You drive too closely to the vehicle in
front of you.

•

Your vehicle is hydroplaning.

•

You take corners too fast.

•

The road surface is poor.

PARKING BRAKE

WARNING

Always set the parking brake fully
and make sure the transmission is
placed in park (P). Failure to set the

parking brake and engage park could result
in vehicle roll-away, property damage or
bodily injury. Turn the ignition to the lock
position and remove the key whenever you
leave your vehicle.

Apply the parking brake whenever your
vehicle is parked. Press the pedal
downward to set the parking brake. The
brake warning lamp in the instrument
cluster will illuminate and remains
illuminated until the parking brake is
released.

To release, pull the brake release lever
located at the lower left side of the
instrument panel.

If you are parking your vehicle on a grade
or with a trailer, press and hold the brake
pedal down, then set the parking brake.
There may be a little vehicle movement as
the parking brake sets to hold the vehicle's
weight. This is normal and should be no
reason for concern. If needed, press and
hold the service brake pedal down, then
try reapplying the parking brake. Chock the
wheels if required. If the parking brake
cannot hold the weight of the vehicle, the
parking brake may need to be serviced or
the vehicle may be overloaded.

HILL START ASSIST

WARNINGS

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) (automatic transmission) or first gear
(1) (manual transmission).

You must remain in your vehicle once
you have activated the system.

During all times, you are responsible
for controlling your vehicle,
supervising the system and

intervening, if required.

If the engine is revved excessively, or
if a malfunction is detected, the
system will be deactivated.

The system makes it easier to pull away
when your vehicle is on a slope without the
need to use the parking brake.

When the system is active, your vehicle will
remain stationary on the slope for two to
three seconds after you release the brake
pedal. This allows you time to move your
foot from the brake to the accelerator
pedal. The brakes release automatically
when the engine has sufficient torque to
prevent your vehicle from rolling down the
grade. This is an advantage when pulling
away on a slope, for example from a car
park ramp, traffic lights or when reversing
uphill into a parking space.

The system will activate automatically on
any slope that will cause significant vehicle
rollback. For vehicles with a manual
transmission, you can switch this feature
off using the information display. See
Information Displays (page 111). The
system will remain on or off depending on
how it was last set.

Note: There is no warning lamp to indicate
the system is either on or off.

Note: If your vehicle is equipped with Auto
Hold, Hill Start Assist will not be available
while Auto Hold is active.

Using Hill Start Assist

1.

Bring your vehicle to a complete
standstill. Keep the brake pedal
pressed and select an uphill gear (for
example, first (1) when facing uphill or
reverse (R) when facing downhill).

2. If the sensors detect that your vehicle

is on a slope, the system will activate
automatically.

3. When you remove your foot from the

brake pedal, your vehicle will remain
on the slope without rolling away for
about two or three seconds. This hold
time will automatically be extended if
you are in the process of driving off.