2003 FORD F750 transmission

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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Exhaust brake (if equipped)
An exhaust brake is an optional
auxiliary braking system that assists
but does not replace the primary
service brake system. An on-off
switch on the instrument panel, in
combination with the accelerator
and clutch pedal switches, allows
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
It is not available with automatic transmissions.
The exhaust brake is a butterfly
type valve mounted in the exhaust
pipe. When the operator’s foot is not
on the accelerator pedal and the
exhaust brake switch is in the ON
position, an air cylinder shuts the
butterfly valve, restricting the flow
of exhaust gases and retarding the
engine. This retarding action is
carried through the engine and drivetrain, slowing the vehicle and
reducing the need for frequent service brake applications.
Exhaust brakes are not intended for use as the primary braking system
during vehicle operation.
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Operation
Push the rocker switch up to turn
the exhaust brake on. The switch
will illuminate in the ON position.
Push the switch down to turn the
brake off.
Starting engine
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 temperatures.
Driving downhill
While approaching a steep grade, make sure that the exhaust brake
switch is in the ON position. The exhaust brake actuates as soon as you
remove your foot from the accelerator pedal. 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 would to ascend the hill.
Before descending a hill or steep grade always select the proper gear. If
the transmission is taken out of gear while descending it is possible that
you will not be able to select another gear because of maximum RPM
being governed.
Make sure the engine speed does not exceed the maximum allowable
engine RPM. Exceeding the maximum allowable engine RPM will 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.
The exhaust brake is not recommended for use on slippery or
low traction road surfaces. Under these conditions a loss of
vehicle control could possibly occur.
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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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The push button shifter has a R
(Reverse), N (Neutral) and D
(Drive) selections as well as a
MODE button, up arrow (for
upshifts) and a down arrow
(downshift) and a digital display.
When a range button is pressed, a
tone will sound, the SELECT
indicator displays a chosen
operation (if the electronic control
unit determines the shift is
acceptable) and the transmission
will shift to the starting range. In D
(Drive), selection of a specific gear
can be accomplished by pressing the
up or down arrow button. If the
CHECK TRANS light (located on the instrument panel) is illuminated,
the shifter control pad may be disabled, tones will not be heard, shifts
may not occur and directional shift changes will not be able to be
performed.
The MODE button may be used to
activate a second shift schedule
(this is typically programmed for
Economywhich will enable the
transmission to shift at a lower RPM
to conserve fuel).
These transmissions incorporate a hold feature to prohibit upshifting
above the gear selected during normal driving. During downhill
operation, the transmission may upshift from the selected gear if the
electronic control unit detects the possibility of engine damage from
exceeding the governed engine speed.
D N R
MODE
D N R
MODE
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Gearshift positions
R (Reverse)- Use this position to
back the vehicle. Completely stop
the vehicle before shifting from R
(Reverse) to any forward gear. The
reverse warning signal will sound
when the selector is in R (Reverse).
Reverse has only one gear and
provides the greatest reduction. The
Select and Monitor indicators will
display R when reverse is attained.
N (Neutral)- Use N (Neutral) for
starting the engine. If the engine
starts in any gear other than N
(Neutral), the start circuit should be
serviced immediately. 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.
The Select and Monitor indicators
will display N.
Do not allow your vehicle to coast in N (Neutral). Transmission
braking is not available in N (Neutral). This practice can also
result in transmission damage.
D N R
MODE
D N R
MODE
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D (Drive)- The vehicle will attain
first gear, and as the speed
increases, the transmission will
automatically upshift through each
gear. As the vehicle slows down, the
transmission will automatically
downshift. The Select indicator will
display the highest gear available.
5th or 4th- 2nd gears (depending on application)- Road conditions,
load or traffic can make it desirable to restrict the automatic shifting to a
lower gear. These positions also provide progressively greater engine
braking for descending grades (the lower the gear, the greater the
braking effect).
The push button selector uses up
and down arrow buttons to select
the desired gear. The select
indicator will display your choice
and the monitor will display the
gear selected.
1st gear- Use for pulling through mud or deep snow, when maneuvering
in tight spaces or when driving up or down steep grades. 1st gear
provides maximum driving power and engine braking.
In case of engine shutdown (i.e - running out of fuel), while the
transmission is in gear, the transmission will remain in gear until the
D N R
MODE
D N R
MODE
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