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 724 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.
When air pressure is insufficient
(below 414 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
0 30 12090 60
150AIR
PRESSUREPSI
!
BRAKE
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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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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
ignition key is turned to the OFF position. After the ignition is turned
off, the transmission will automatically shift to N (Neutral) and the
D N R
MODE
D N R
MODE
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136
monitor on the shift pad will display N (Neutral) when the ignition key is
turned to the ON position.
Allison 2000 series
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 five forward speeds in four ranges and one
reverse range.
R (Reverse)
Use this position to back the vehicle. Completely stop the vehicle before
shifting from R (Reverse) to any forward gear (1, 2, 4 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.
Do not allow your vehicle to coast in N (Neutral). Engine
braking is not available in N (Neutral). Allowing your vehicle to
coast in N (Neutral) may result in loss of vehicle control and severe
internal transmission damage.
D (Drive-Normal driving position)
In this position, the transmission starts in first gear and automatically
shifts through second, third, fourth and fifth depending on load and
speed demands. When the vehicle is slowing down, the transmission will
automatically downshift. This range is used for highway driving under
normal conditions.
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4 and 2 (Fourth 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. Use this position when pulling through mud or
snow, driving up steep grades, hauling extra heavy loads or where
maximum reduction is required.
Allison 2400 series
This transmission provides five forward speeds in four ranges and one
reverse range.
P (Park)
Use this position when you start the engine. The engine is designed to
start in the P (Park) or N (Neutral) position only.
Always come to a complete stop before shifting into P (Park). Make sure
the gearshift is securely latched in P (Park). This position locks the
transmission and prevents the rear wheels from turning.
Always set the parking brake fully and make sure the gearshift
lever is latched in P (Park). Turn off the ignition whenever you
leave your vehicle.
When parking on hilly or off-road terrains, be sure to set the parking
brake fully and chock the wheels to prevent unexpected and possibly
sudden vehicle movement.
R (Reverse)
Use this position to move the vehicle backwards. Completely stop the
vehicle before shifting from a forward gear (1, 2, 4 or D) to R (Reverse),
or 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 gear reduction.
N (Neutral)
This position can be used when starting the engine. The engine is
designed to start in the P (Park) or N (Neutral) position only. The
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To go backward
Reverse is obtained by putting the
gearshift lever in R (Reverse) and
engaging the clutch while pressing
lightly on the accelerator.
Removing key from ignition
²Turn the ignition key to position
2.
²Push the release lever forward
and rotate the key towards you
and remove.
Power-take off operation (PTO) with a manual transmission
Transmission-mounted power take-off units are available for local
installation on Ford vehicles. See your Body Builder's Layout Book for
restrictions on use and installation of power take-off units.
To engage the PTO unit, stop the vehicle and place the transmission
control in neutral. Depress the clutch and allow the gears to stop
rotating, then engage the PTO unit. The PTO can also be selected with
the transmission in gear as long as the clutch is depressed.
When operating the PTO unit with the vehicle stationary, first set the
parking brake (chock the wheels if the vehicle is on a hill or other
unlevel surface).
2 4 6
3 5 7
1 R
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When split shifting, the axle shift control must stay UP in the
HIGH range until after any transmission lever movement.
A 2±speed axle should NEVER be shifted on a downgrade.
To downshift the axle from HIGH to LOW range, either the ring gear has
to speed up by one-third, or the wheels have to slow down by one-third
to allow for synchronization. When you are on a down grade, the wheels
will not slow down, but will tend to speed up. As a result, the ring gear
must be accelerated to synchronize speeds. You are however limited in
doing so by your engine governed speed, and may not be able to reach
synchronization to allow the shift to take place. If the shift is not
completed , the axle will be in neither HIGH nor LOW range and all
driveline retardation will be lost.
Ratio extender use
Low End
A 2±speed axle can be used as a ratio-extender when split shifting is not
necessary. For low end use, just shift the axle into the LOW to start out,
and shift to HIGH when the extra torque is no longer needed.
Transmission (5-speed) 1st 1st 2nd 3rd 4th 5th 6th
2-speed Axle Axle
LowAxle High
High End
To use the 2±speed axle as a high end ratio-extender, stay in the LOW
range for normal upshifts and only shift the axle to HIGH on the freeway
for greater road speed.
Transmission (5-speed) 1st 2nd 3rd 4th 5th 6th
Speed
Axle
High 2-Speed Axle Low for Gradeability
DRIVING THROUGH WATER
Do not drive quickly through standing water, especially if the depth is
unknown. Traction or brake capability may be limited and if the ignition
system gets wet, your engine may stall. Water may also enter your
engine's air intake and severely damage your engine.
If driving through deep or standing water is unavoidable, proceed very
slowly. Never drive through water that is higher than the bottom of the
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