2003 FORD F750 wheel

Parking brake warning chime—F650 SuperCrewzer
If a chime sounds when pulling the 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—F650 SuperCrewzer
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.
Burnish procedure—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.
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Cam brakes—automatic 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.
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.
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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.
Parking brake control
Pull the yellow parking brake knob
out to apply the parking brake. Push
the knob in to release the parking
brake.
This control is used for
parking only. Do not leave
the vehicle unattended after
setting the parking brake without
placing the transmission in R
(Reverse) for manual transmission
or N (Neutral) for automatic
transmission. Use of wheel chocks
is also recommended in hilly or
off-road usage.
Releasing spring brake with air pressure
The air system in all vehicles with spring-actuated rear wheel parking
brakes is equipped with a tank valve located on the supply or service air
tank for connection to an outside air supply. The valve permits the
system to be recharged with air from an outside source, releasing the
spring-actuated parking brakes. The vehicle may then be towed in an
emergency.PARKING
BRAKE
PULL TO
RELEASE
APPLY
PUSH TO
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An outside air source can be used only if the protected system is in
operating condition. If air pressure cannot be restored in the protected
air system, the spring-actuated brakes must be released manually.
Releasing spring brake manually
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.
Impact wrenches should not be used as they may damage the piston and
prevent proper caging of the spring. Do not apply more than 68 Nm
(50 lb-ft) torque to the release bolt nut.
1. Remove the stud tool and nut
from the carrying pocket on the
brake chamber assembly.
2. Remove the access plug from the
end of the spring chamber.
3. Insert the release stud through
the opening in the chamber and into
the spring pressure plate.
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Drain all the air brake reservoirs
daily, completely to 0 kPa/psi, by
opening the draincock at the bottom
of the tanks. Close draincock after
complete draining. Air tanks
equipped with automatic moisture
ejector valves may also be drained
manually as required to maintain a
dry air system. Contact your dealer
if you are unsure of the air reservoir
locations or the draining procedure.
STEERING
Your vehicle is equipped with power steering. Power steering uses energy
from the engine to decrease the driver’s effort in steering the vehicle.
Never hold the steering wheel to the extreme right or the extreme left
for more than a few seconds when the engine is running. This action
could damage the power steering pump.
Suspension and steering
The suspension and steering linkage in your vehicle should be inspected
periodically for the following:
•Spring leaf damage
•Spring sag
•Abnormal looseness
•Damaged seals
The following changes indicate a need to inspect and service your
vehicle:
•Changes in steering action
•Hard steering
•Excessive free play
•Unusual sounds when turning or parking
If the steering wanders or pulls
This condition can be caused by any of the following conditions:
•Underinflated tire(s) on any wheel(s)
•Front end out of alignment
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•Total vehicle out of alignment (i.e. rear axle[s] out of alignment with
front axle)
•Improper adjustment in the steering gear
•Vehicle overloaded or unevenly loaded
•High crosswinds
•High crown in center of road
•Components in steering linkage loose or worn
•Wheel bearings improperly adjusted
•Excessive lash in steering shaft or universal joints
If the vehicle steers hard
Hard steering can be caused by any of the following conditions:
•Underinflated tire(s) on any wheel(s)
•Vehicle overload
•Misalignment of the front tires
•Lack of lubricant in the front spindle bearings or linkage components
•Low oil level in the power steering system
•Broken or loose power steering pump direct drive connection
•Malfunctioning relief valve in power steering gear or steering pump
•Malfunctioning power steering pump
•Restriction in power steering lines
•Improperly set turn stops
•Air entrapped in power steering system fluid
AIR SUSPENSION SYSTEM (IF EQUIPPED)
The on-highway air suspension system is designed to provide a superior
ride, outstanding driver comfort while minimizing wear on the cab, frame
and payload.
The height control valve automatically keeps the vehicle at a constant
level due to load changes and uneven road surfaces.
Air suspension-equipped vehicles are equipped with a dryer module
which needs to be opened monthly to remove moisture from the system.
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Air suspension dump valve
The dump valve switch activates the
dump valve. The dump valve
releases air from the air springs and
lowers the rear suspension, allowing
you to back under a low trailer
when necessary.
DRIVING WITH AN AUTOMATIC TRANSMISSION (IF EQUIPPED)
Allison automatic transmission
Do not allow your vehicle to coast in N (Neutral). Transmission
braking is not available in N (Neutral). Allowing the vehicle to
coast in N (Neutral) could result in loss of vehicle control and severe
transmission damage.
The Allison automatic transmissions are a torque converter type, full
power shifting and fully automatic. They also have the added flexibility
of manually selecting and holding in the lower drive ranges which permit
the drive selection of the most suitable gear range to match varying road
and load conditions. To prevent destructive overspeeding of the engine,
the hold feature is not infinite, resulting in upshifts from the hold range
to the next higher range at some speed above the no-load governed
speed of the engine.
Allison AT-545
These transmissions have no P (Park) position. Before leaving
the driver’s seat, always shift into N (Neutral) and set the
parking brake. Shut off the engine and remove your ignition key.
Always use wheel chocks for hilly or off-road parking. Unexpected and
possibly sudden vehicle movement may occur if these precautions are
not taken.
This transmission provides four forward speeds and one reverse range.
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R (Reverse)
Use this position to back the vehicle. Completely stop the vehicle before
shifting from R (Reverse) to any forward gear (1, 2, 3 or D). The reverse
warning signal will sound when the selector is in R (Reverse). Reverse
has only one gear and provides the greatest gear reduction.
N (Neutral)
Place the selector in N (Neutral) before starting the engine. Shift to N
(Neutral) and set the parking brake any time the engine is to be running
while the operator is not at the controls. The engine should be at idle
speed when any shift from N (Neutral) to a drive range is made.
D (Drive-Normal driving position)
The transmission starts in first gear and automatically shifts through
second, third and fourth depending on load and speed demands. This
range is used for highway driving under normal conditions.
3 and 2 (Third and Second)
Use these ranges when road, load or traffic conditions require a lower
gear. These ranges provide greater engine braking than D (Drive). When
conditions are improved that no longer require these lower gears, shift
back to D (Drive).
1 (First)
The transmission has to be manually shifted into 1 (First) and will not
shift into a higher gear. This range is used for extra heavy loads or where
maximum reduction is required.
Allison MD Series transmissions
These transmissions have no P (Park) position. Before leaving
the driver’s seat, always shift into N (Neutral) and set the
parking brake. Shut off the engine and remove your ignition key.
Always use wheel chocks for hilly or off-road parking. Unexpected and
possibly sudden vehicle movement may occur if these precautions are
not taken.
These transmissions are electronically controlled and have a push button
shifter. MD transmissions are available in five- or six-speed driving
ranges.
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