Ford F-650/750 (2018 year). Manual — part 29

WARNING

Sudden accelerations on slippery
surfaces could cause the wheels to
spin, the vehicle to turn sideways on

a crowned road surface or in a turn,
possibly resulting in loss of vehicle control
and personal injury.

Activating the Locking Differential

You can lock and unlock the differential
when your vehicle is moving at a constant
speed of less than 25 mph (40 km/h) and
while the wheels are not slipping. Do not
lock the differential when your vehicle is
traveling down steep grades and when
traction is minimal.

The differential lock and differential lock
light automatically disengage at speeds
above 25 mph (40 km/h). The differential
lock remains off until either you restart your
vehicle or you turn the differential lock
switch off then back on.

Servicing a Vehicle with a Locking
Differential

Turn the engine off and raise all drive
wheels of the locker differential axle in
order to prevent your vehicle from moving
when servicing the wheels, tires or brakes.
Axles equipped with a driver-controlled
differential deliver power to both wheels
even when only one wheel is on the ground.

WARNING

Failure to raise all drive wheels with
this type of differential could cause
the vehicle to move unexpectedly,

resulting in property damage, personal
injury or death.

2-SPEED REAR AXLE

(If Equipped)

WARNING

Never shift a two-speed axle when
descending a steep grade as this
may cause loss of vehicle control and

result in personal injury.

Note: Do not shift between ranges when
the speed control is on.

A two-speed rear axle allows the driver to
select a low range for greater pulling power
and a high range for greater road speed
and fuel economy. You can also use these
ranges to provide extra steps between
transmission shifts when driving on steep
grades or fuel economy may be factors.

Axle Shifting

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Note: Do not shift the axle to LOW when
your vehicle is moving. Use LOW when you
drive a fully loaded vehicle on a severe grade
or in congested traffic. Use HIGH for all
normal driving conditions with a lightly
loaded or partially loaded vehicle.

Note: The axle is set to HIGH by default.

To shift the axle between HIGH and LOW
with the vehicle stopped, place the
transmission in position N, then press and
hold the button for two seconds.

GENERAL INFORMATION

WARNINGS

Do not drive with your foot resting on
the brake pedal. This results in
abnormally high brake temperatures,

excessive lining wear and increased
stopping distance.

Continuous application of the brakes
causes the brakes to overheat,
resulting in temporary loss of braking.

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.

All standard equipment brakes are
self-adjusting. Automatic adjustment,
when required, occurs whenever you apply
and release the brakes during forward or
reverse operation.

Know the required stopping distances for
all driving conditions you may encounter.
For longer brake lining life, take full
advantage of engine braking power when
coming to a stop.

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See Warning Lamps and
Indicators (page 60).

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.

If brakes do not grip well:
•

Check brake adjustment.

•

Check brake linings for excessive wear.

•

Check system air pressure on vehicle
equipped with air brakes.

•

Let the brakes cool if you have been
using them excessively, as in mountain
driving or after several fast, high-speed
stops.

•

If you have been driving through deep
water, gently apply the brakes several
times while your vehicle is moving
slowly.

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

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 turn 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.

E209041

If the system is disabled, normal
braking is still effective. If the
brake warning lamp illuminates

when you release the parking brake, have
the system checked by an authorized
dealer.

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If you connect a PLC trailer with
the ignition on, the trailer ABS
light also illuminates. If the light

fails to illuminate, if it remains on after you
start the vehicle or continues to flash, have
the system serviced immediately.

HINTS ON DRIVING WITH
ANTI-LOCK BRAKES

The anti-lock braking system does 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.

Note: If the system activates, 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.

PARKING BRAKE

Hydraulic Brakes

(If Equipped)

WARNINGS

Always set the parking brake and
leave your vehicle with the
transmission in park (P).

This control is for parking only. Do
not leave the vehicle unattended
after setting the parking brake

without placing the transmission in park
(P). We recommend using wheel chocks
for hilly or off-road circumstances.

Unexpected and possibly sudden
vehicle movement may occur if you
do not take these precautions.

WARNINGS

If the parking brake is fully released,
but the brake warning lamp remains
illuminated, the brakes may not be

working properly. Have your vehicle
checked as soon as possible.

Apply the parking brake whenever the
vehicle is parked. To set the parking brake,
pull the handle up until it snaps into the
locked position.

When the parking brake is out of
adjustment, seek service immediately.

E208810

The parking brake warning lamp
in the instrument cluster
illuminates, and remains

illuminated (when you switch on the
ignition), until you release the parking
brake.

E210347

Push the palm release lever (A) on the
parking brake handle (B) and push down
as far as possible to release the brake.
Driving with the parking brake on causes
the brakes to wear out quickly and reduces
fuel economy.

We recommend you not use the parking
brake to stop a moving vehicle. However,
if the normal brakes fail, you can use the
parking brake to stop your vehicle in an
emergency. Since the parking brake only
applies retardation to the rear wheels, the
vehicle's stopping distance increases
greatly and the handling of your vehicle is
adversely affected.

Releasing Spring Manually

WARNINGS

Do not attempt to disassemble the
parking brake air chamber under any
circumstances as this may cause

serious injury.

Block the wheels to help prevent the
vehicle from moving.

Unexpected and possibly sudden
vehicle movement may occur if you
do not take these precautions.

If you release hydraulic pressure from the
spring brake chamber, the power spring
applies the brake. If the hydraulic pressure
can be re-established, you must release
the spring brake in order to move your
vehicle.

Air Brakes

(If Equipped)

WARNING

This control is for parking only. Do
not leave the vehicle unattended
after setting the parking brake

without placing the transmission in park
(P). We recommend using wheel chocks
for hilly or off-road circumstances.

If the service brakes fail to operate while
your vehicle is moving, you can make an
emergency stop with the parking brake.
Since the parking brake only applies
stopping power to the rear wheels, your
vehicle’s stopping distance greatly
increases and the handling of your vehicle
is adversely affected. Make repairs
immediately to an inoperative air brake
system circuit.

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Pull the yellow, dash-mounted parking
brake knob to apply the parking brake.

E208810

The parking brake light
illuminates and remains
illuminated (when you switch

the ignition to the on position) until you
release the parking brake.

Releasing the Parking Brake

WARNING

When your vehicle is stationary, keep
the brake pedal fully pressed when
shifting gears. Failure to follow this

instruction could result in personal injury,
death or property damage.

Note: Read and understand the following
steps and perform them whenever you
prepare to drive the vehicle.

Note: The parking brake does not disengage
unless sufficient system air pressure is
available.

1.

Press and hold the service brake pedal
while the engine is running.

2. Select the appropriate drive gear.

3. Push and hold the yellow

dash-mounted parking brake knob until
the parking brake light turns off, then
release.