2017 FORD F750 brake

FULL POWER BRAKE
WARNING
If the brake warning lamp in the
instrument cluster remains
illuminated after engine start up, this
indicates a system failure in the Full Power
Brake system. Stop the vehicle safely as
soon as possible and seek service
immediately. This system incorporates standard braking,
an anti-lock braking system (ABS) and
optional Power Park Brake into one fully
integrated hydraulic brake system. With
the Full Power Brake system, braking
energy is stored, similar to an air brake
system, resulting in faster response times
and shorter stopping distances. This is
accomplished using motor and pump
assemblies that pressurize the system by
pumping brake fluid into accumulators.
This is similar to the air compressor of an
air brake system pressurizing the air tanks.
The system includes a master cylinder that
provides the normal pedal feel and
transfers the pedal force, via brake fluid,
to the main components of the system.
Note:
The motor and pumps run
momentarily with the ignition switch in the
on or run position, or in the off position with
the brake pedal pressed.
Note: During normal driving, you may hear
the pump and motors replenishing the
accumulators. This is a normal function of
the system. AIR BRAKES WARNINGS
Do not drive or continue to drive if the
low air pressure buzzer is sounding
or the brake warning light is lit. These
warnings indicate that air pressure is not
to normal operating level. Continued use
of the vehicle could result in loss of braking
ability. Avoid repeated light application of
the brake pedal. This depletes air
pressure faster and could result in
loss of braking capability. Do not move the vehicle when the
air pressure is insufficient because
the brake system may be inoperative.
After starting the engine, give the air
compressor time to build up the air
pressure to 60 psi (414 kPa) before moving
your vehicle. Periodically check the air pressure gauge
while driving. Pressure should range
between approximately 100 psi (690 kPa)
to
130 psi (896 kPa). The air compressor
governor cut-in and cutout pressure
settings are set at the factory and are not
adjustable.
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When air pressure is insufficient
(below 60 psi (414 kPa)), a
warning light illuminates and a
buzzer sounds when the ignition is in the
on position. This may happen because
excessive brake applications are depleting
the system air pressure. If this condition
occurs, stop driving your vehicle until the
compressor has fully recharged the air
system.
Select a gear ratio to help slow your vehicle
before descending grades. Supplementing
with brakes, as required, help to safely slow
the vehicle and avoids overspeeding the
engine.
Air Chamber Stroke Indication
Air chamber push rods have orange stroke
indicator markers that warn when the
braking system requires adjustment or
repair. The painted orange indicator is on
the air chamber push rod at the slack
adjuster stroke dimension that requires
service when visible during brake
application.
A qualified service technician should
perform air brake inspection and
adjustment or repairs keeping to the
instructions in the service manual.
Cam Brakes - Automatic Slack
Adjusters WARNING
Do not manually adjust the
automatic slack adjusters to correct
excessive push rod stroke as it may
result in reduced brake effectiveness and
a vehicle crash. Excessive push rod stroke
indicates that a problem exists with the
automatic adjuster, with the installation
of the adjuster, or with foundation brake
components that manual adjustment does
not remedy. Seek service from a qualified
facility for excessive push rod stroke. Standard air brakes (cam) are equipped
with automatic brake adjusters. Automatic
adjustment occurs during brake
applications. Inspect brakes for proper
adjustment at the specified intervals. See
Scheduled Maintenance
(page 316).
Emergency Air Brake WARNING
Do not continue to operate the
vehicle with a failure of one of the
brake systems. Take the vehicle to
your dealer for service immediately. All vehicles are equipped with a dual brake
system. In the unlikely event of a failure of
one system, the second system functions
for emergency stopping. The brake pedal
controls all these systems in the same
manner as for normal stops.
EXHAUST BRAKE
WARNING
The exhaust brake is not
recommended for use on slippery or
low traction road surfaces. Under
these conditions a loss of vehicle control
could occur. 124
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Note:
Installing an exhaust or auxiliary
brake does not necessarily protect the
engine from exceeding maximum governed
speed. Use the primary brakes to make sure
the engine never exceeds maximum
governed speed under any circumstance.
Note: Before starting the engine, make sure
that the exhaust brake switch is in the off
position. Do not turn the exhaust brake on
until the engine has reached normal
operating temperature.
Note: Maximum exhaust brake
performance relates to the type of
transmission your vehicle has.
Note: Engine speed has a major influence
of retarding performance. When engine
speed stays at the maximum allowable
level, the exhaust brake operates at peak
performance.
Note: Exhaust brakes operate effectively
with automatic transmissions, but
performance varies with engine speed and
the gear selected by the transmission.
An exhaust brake is an auxiliary braking
system that assists, but does not replace,
the primary service brake system. It helps
control vehicle speed; it is not a
vehicle-stopping device. A switch on the instrument panel, in
combination with the accelerator and
clutch pedal, allow the operator to make
maximum use of the exhaust brake in the
following conditions:
•
Off-highway driving.
• Mountain driving.
• Heavy traffic.
• High-speed highway driving.
To switch the brake on, push the switch
up. Push the switch down to turn it off.
While approaching a steep grade, make
sure that the exhaust brake switch is in the
on position. The exhaust brake begins
working as soon as you remove your foot
from the accelerator pedal.
Before descending a hill or steep grade,
always select the proper gear. If you take
the transmission out of gear while
descending, it is possible that you cannot
select another gear because of maximum
governed RPM.
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Make sure the engine speed does not
exceed the maximum allowable engine
RPM. Exceeding the maximum allowable
engine RPM can result in damage to the
engine. Apply the service brakes to reduce
the engine RPM or make a slower descent
by using a lower gear.
While going down the grade, use a low
enough gear to descend safely with a
minimum application of the service brakes.
As a general guideline, use the same gear
as you use to ascend the hill.
Exhaust Brake Operating
Characteristics
The exhaust brake turns on when you
remove your feet from both the accelerator
and clutch pedals and the exhaust brake
switch is in the on position. The following
conditions exist if the brake is operating
properly:
•
A slight change in engine sound when
the exhaust brake turns on.
• A smooth braking effect. Do not expect
a retarding effect similar to sudden,
hard application of the service brakes.
• The retarding force possibly felt acting
against your body during brake
application (depending on the grade
and vehicle load). This force is actually
preventing the vehicle from going much
faster.
• Engine temperature remaining in the
normal operating range.
• The tachometer showing a drop in
engine RPM (depending on grade and
vehicle load) during a descent.
• A decrease in road speed when
applying the exhaust brake during a
descent, except when your vehicle is
carrying a heavy load or the grade is
extremely steep. In these instances,
you may need to apply the service
brakes occasionally. TRAILER BRAKES
Trailer Brake Hand Control (If Equipped) WARNING
The hand control should never be
used to apply the brakes when the
tractor and trailer are parked
unattended. Air may leak from the system
and the vehicle could possibly move,
resulting in possible property damage,
personal injury or death. The hand control is located on the
right-hand side of the instrument panel. It
applies the trailer service brakes, which are
independent of the truck or tractor service
brakes.
It operates a valve that provides gradual
control of air pressure applied. When the
valve is only partially applied, you can
override the trailer brakes by pressing fully
on the brake pedal.
To apply the trailer brakes using the hand
control, move the lever downward. The
further you push the lever down, the
greater the air pressure is applied to the
brakes. The lever remains in place until
manually moved.
To release the trailer brakes, move the
lever up completely.
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F-650/750 (TBC) , enUSA, First Printing BrakesE210339

Trailer Air Supply and Parking
Brake Modular Controls (If Equipped)
The trailer air supply valve delivers air to
the trailer supply and automatically pops
out, shutting off the trailer supply, if
pressure decreases to approximately 35 psi
(249 kPa)
. The parking brake controls the spring
brakes on the tractor. When you pull the
knob out, it causes the trailer supply valve
to pop out, applying both the tractor and
trailer parking brakes. You can
independently release the trailer brakes by
pushing only the trailer air supply valve in.
Initial Charge With the air system completely discharged,
both knobs (A and B) are out. When the
air pressure reaches
70 psi (481 kPa), the
trailer air supply (A - red knob) may be
pushed in and should stay in, charging the
trailer air system and releasing the trailer
brakes. You can push in the parking brake (B -
yellow knob) and supply air to the tractor
spring brakes, releasing them.
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A
B
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Normal Driving Position Push in both knobs (A and B) to supply air
to both trailer and tractor spring brakes,
releasing all brakes.
System Park With both knobs (A and B) pushed in
(normal driving position), the parking
brakes for both the tractor and trailer can
be applied by pulling the parking brake
knob (B) out, exhausting air from the
tractor spring brakes, simultaneously
causing the trailer air supply valve to pop
out, applying the trailer brakes.
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Trailer Charge
If both knobs (A and B) are out, and you
want to recharge the trailer while leaving
the tractor spring brakes applied, the trailer
air supply (A) can be pushed in to recharge
the trailer air supply line. You can also use
this mode to park a combination vehicle
with tractor spring brakes.
Automatic Application
If both knobs (A and B) are pushed in and
the brake system air pressure is reduced
to approximately 35 psi (249 kPa), the
trailer air supply (A) knob automatically
pops out applying the emergency or
parking brakes on the trailer. If the trailer
air supply (A) knob is manually held in and
the air pressure is reduced to
approximately
30 psi (207 kPa), a tripper piston within the valve moves, exhausting
the trailer air supply, applying the trailer
brakes. Further reduction of air pressure,
while holding the trailer air supply knob in,
causes the parking brake knob to pop out
at
25 psi (172 kPa).
Actuation of Trailer Park (Emergency)
or Tractor Bobtail Position To actuate the trailer brakes only, pull out
the trailer air supply (A) knob. This applies
the trailer brakes whether the trailer uses
emergency or spring brakes.
You can also use this mode when the
tractor or truck with trailer is used during
bobtail operation.
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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.
Note:
The system does not apply the brakes
when vehicle speed is above 25 mph
(40 km/h).
USING TRACTION CONTROL -
VEHICLES WITH: AIR BRAKES WARNING
Aggressive driving in any road
conditions can cause you to lose
control of your vehicle increasing the
risk of severe personal injury or property
damage. The occurrence of a traction
control event is an indication that at least
some of the tires have exceeded their
ability to grip the road; this may lead to an
increased risk of loss of vehicle control,
vehicle rollover, personal injury and death.
If you experience a severe road event,
SLOW DOWN. Use the traction control switch on the
instrument panel to select Off Road or
Mud/Snow traction mode.
This is beneficial when your vehicle is stuck
in snow or on a slippery road surface. This
mode allows excess wheel spin to dig your
vehicle out and allows you to rock your
vehicle.
Press the switch again to select standard
traction control. The system automatically
selects standard traction control at the
next ignition cycle. System Indicator Light
Note:
If the traction control light does not
flash during a traction control event or stays
illuminated, the system is not functioning
properly. Take your vehicle to an authorized
dealer for service.
During traction control operation, the
traction control light flashes rapidly and
the engine does not rev-up when you press
further on the accelerator. This is normal
and is no reason for concern.
In Off Road or Mud/Snow mode, the
traction control light illuminates and
flashes slowly. If a traction event occurs in
either mode, the light flashes rapidly.
USING TRACTION CONTROL -
VEHICLES WITH: HYDRAULIC
BRAKES WARNING
Aggressive driving in any road
conditions can cause you to lose
control of your vehicle increasing the
risk of severe personal injury or property
damage. The occurrence of a traction
control event is an indication that at least
some of the tires have exceeded their
ability to grip the road; this may lead to an
increased risk of loss of vehicle control,
vehicle rollover, personal injury and death.
If you experience a severe road event,
SLOW DOWN. The system automatically turns on each
time you switch the ignition on.
Use the traction control switch on the
instrument panel to switch the system off
or on.
If your vehicle is stuck in mud or snow,
switching traction control off may be
beneficial as this allows the wheels to spin.
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F-650/750 (TBC) , enUSA, First Printing Traction Control