2001 FORD F750 brake

Hydraulic brake booster system (Hydromax)
The Hydromax systems receive fluid pressure from the power steering
pump to provide power assist during braking.
The Hydromax booster receives backup pressure from the reserve
system electric pump whenever the fluid in the power steering system is
not flowing. When the engine is OFF, the pump will turn on if the brake
pedal is applied, or if the ignition is turned to the ON position.
The sound of the pump operating may be heard by the driver, but this is
a normal characteristic of the system.
The reserve system provides reduced braking power, so the vehicle
should be operated under these conditions with caution, and only to seek
service repair and remove the vehicle from the roadway.
For Hydromax under normal operating conditions noise of the fluid
flowing through the booster may be heard whenever the brake is applied.
This condition is normal. Vehicle service is not required.
If braking performance or pedal response becomes very poor, even when
the pedal is strongly applied, this may indicate the presence of air in the
hydraulic system or fluid leakage. Stop the vehicle safely as soon as
possible and seek service immediately.
If the red BRAKE warning lamp in
the instrument cluster remains
illuminated after engine start up,
this indicates a system failure in the
master cylinder of the brake system.
Stop the vehicle safely as soon as possible and seek service immediately.
If the yellow BRAKE RESERVE
(E-motor) warning light remains on
while the engine is running, this
indicates inadequate hydraulic
booster pressure or reserve pump
system failure. Stop the vehicle safely as soon as possible and seek
service immediately.
!
BRAKE
BRAKE
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109

Parking brake
Apply the parking brake whenever
the vehicle is parked. To set the
parking brake, pull handle up until it
snaps into the locked position.
A properly adjusted parking brake
requires approximately 116 Nm
(90 lb-ft) to activate. For maximum
parking brake effectiveness turn
handle clockwise to adjust for wear.
When the parking brake is out of
adjustment, seek service
immediately.
The parking BRAKE warning lamp
in the instrument cluster illuminates
and remains illuminated (when the
ignition is turned ON) until the
parking brake is released.
Do not use the gearshift selector in place of the parking brake.
Always set the parking brake fully AND make sure the gearshift
selector is in R (Reverse) for vehicles equipped with manual
transmission, P (Park)(if equipped)or N (Neutral) for vehicles with
automatic transmission. Use of wheel chocks is also recommended in
hilly or off-road usage.
Unexpected and possible sudden vehicle movement may occur if
these precautions are not taken.
P
BRAKE
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110

The parking brake is not recommended to stop a moving vehicle.
However, if the normal brakes fail, the parking brake can be used to stop
your vehicle in an emergency. Since the parking brake only applies
retardation to the rear wheels, the vehicle's stopping distance will
increase greatly and the handling of your vehicle will be adversely
affected.
Push the palm release lever on the
parking brake handle and push
down as far as possible to release
the brake. Driving with the parking
brake on will cause the brakes to
wear out quickly and reduce fuel
economy.
Parking brake Ð F650 SuperCrewzer only
Pull the yellow parking brake knob
out to apply the parking brake. Push
the knob in to release the parking
brake.
PARKING
BRAKE
PULL TO
RELEASE
APPLY
PUSH TO
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111

Parking brake warning chime Ð F650 SuperCrewzer Only
If a chime sounds when pulling the yellow knob out, your parking brake
is not functioning properly, seek service immediately. This chime will
sound until the yellow knob is pushed in or eight minutes have passed. If
the yellow knob is pulled out again the chime sounds as a reminder that
immediate service is required to the parking brake system.
Releasing spring brake manually Ð F650 SuperCrewzer Only
Do not attempt to disassemble the parking brake chamber under
any circumstances. The high spring load may cause serious
injury if the chamber clamps are removed.
If air pressure is released from the spring brake chamber the power
spring applies the brake and, unless air pressure can be re-established,
the spring brake must be released as follows in order to move the
vehicle.
Block the wheels to prevent the vehicle from moving.
Unexpected and possibly sudden vehicle movement may occur if
these precautions are not taken.
Remove the clevis which is attached
to the end of the spring chamber
rod. This can be done by using a
wrench on the flats of the rod to
thread it out of the clevis. There is
sufficient thread length in the clevis
to fully release the parking brake.
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112

Burnish procedure Ð All except F650 SuperCrewzer
For optimal performance of a new parking brake system/new linings
perform the following procedure:
1. While driving the vehicle at 40 km/h (20 mph) apply the parking brake
(with applicable force to set to approximately 18kg [40 lbs.]). Allow the
vehicle to come to a complete stop.
2. Release the parking brake, drive 16.8 km (1.5 miles) to cool the brakes.
3. Repeat steps 1 through 2 ten times.
AIR BRAKES (if equipped)
Foot service brakes
Air brakes are operated by a
standard dash-mounted foot pedal.
All standard equipment brakes are
designed to be self-adjusting.
Automatic adjustment, when
required, occurs whenever the
brakes are applied and released
during forward or reverse operation.
Know the required stopping
distances for all driving conditions
that may be encountered. For longer brake lining life, take full advantage
of engine braking power when coming to a stop.
Before descending a long or steep hill, shift to a lower gear and avoid
continuous application of the brakes.
Do not drive with your foot resting on the brake pedal. This will
result in abnormally high brake temperatures, excessive lining
wear and increased stopping distances.
Continuous application of the brakes will cause the brakes to
overheat, resulting in a temporary loss of braking.
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113

Occasional or intermittent brake squeal may result from environmental
conditions such as cold, hot, wet, snow, salt, mud, etc. This condition will
not affect braking effectiveness. The brakes should be checked only if
squeal occurs continuously with every application.
If brakes do not grip well
²If you have been driving through deep water, gently apply the brakes
several times while the vehicle is moving slowly.
²Let the brakes cool if you have been using them excessively, as in
mountain driving or after several fast, high speed stops.
²Check brake adjustment.
²Check brake linings for excessive wear.
²Check system air pressure.
Air brakes
After starting the engine, give the air compressor time to build up the air
pressure to 414 kPa (60 psi) before moving the vehicle.
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 will
deplete air pressure faster and could result in loss of braking
capability.
Periodically check the air pressure
gauge while driving. Pressure should
range between approximately 703 to
930 kPa (105-135 psi). The air
compressor governor cut-in and
cut-out pressure settings are preset
at the factory and are not
adjustable.
0 30 12090 60
150AIR
PRESSUREPSI
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114

When air pressure is insufficient
(below 534 kPa [60 psi]), a warning
light illuminates and a buzzer
sounds when the ignition is in the
ON position.
This condition may be caused by excessive brake applications depleting
the system air pressure. If this condition occurs, stop driving the vehicle
until the compressor has fully recharged the air system. Do not move the
vehicle in this condition because the brake system may be inoperative.
Select a gear ratio to help slow your vehicle before descending grades.
Supplement with brakes as required to safely slow the vehicle and avoid
overspeeding the engine.
Air chamber stroke indication
All Ford air chamber push rods have orange stroke indicator stripes that
alert the operator when the braking system requires adjustment or
repair. The orange stripe is painted on the air chamber push rod at the
slack adjuster readjustment stroke dimension.
Air brake inspection and adjustment should be performed by a qualified
service technician in accordance with the instructions in the Ford Truck
Service Manual.
Cam brakesÐautomatic slack adjusters
Standard air brakes (cam) are
equipped with automatic brake
adjusters. Automatic adjustment
occurs during forward and reverse
brake applications. Inspect brakes
for proper adjustment at the
intervals listed in the vehicle Service
Maintenance Guide.
!
BRAKE
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115

Emergency air brake
All vehicles are equipped with a dual brake system. In the unlikely event
of a failure of one system, the second system will function for emergency
stopping. These systems are all controlled by the brake pedal in the
same manner as for normal stops.
Do not continue to operate the vehicle with a failure of one of
the systems. Take the vehicle to your dealer for service
immediately.
Anti-lock braking system (if equipped)
For information on the anti-lock braking system (ABS), refer to
Hydraulic brakesin this chapter.
Driving with ABS
Maintain a steady brake pedal application; you do not need to pump or
remove your foot from the pedal. The ABS keeps the wheels rolling
during braking to maintain control and reduce stopping distances. For
information on the anti-lock braking system (ABS), refer toHydraulic
brakesin this chapter.
Parking brake
Do not use the gearshift selector in place of the parking brake.
Always set the parking brake fully AND make sure the gearshift
selector is in R (Reverse) for vehicles equipped with manual
transmission or N (Neutral) for vehicles with automatic transmission.
Unexpected and possible sudden vehicle movement may occur if
these precautions are not taken.
If the service brakes should fail to operate while the vehicle is in motion,
you can make an emergency stop with the parking brake. The stopping
distance, however, will be much greater than normal. Repairs should be
made immediately to an inoperative air brake system circuit.
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