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.
4. Turn the release stud one-quarter
turn to engage the stud tangs with
the slot in the pressure plate. Keep
the stud engaged and install the nut
on the release stud.
5. Tighten the nut until the spring is
fully caged and the brakes are
released. Do not loosen or remove
the release stud and nut unless the brake chamber is completely
assembled and is securely clamped.
6. When the air pressure is restored, unscrew and remove the release
stud and install in the carrying pocket. Install the access plug.
Trailer brake (if equipped)
During normal operation, the trailer brakes operate whenever the tractor
brakes are applied. A manual control lever is provided so the trailer
brakes can be applied separately, if required. To apply the trailer brakes,
pull the trailer brake control downward to the APPLIED position.
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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 help steer 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:
²Spring leaf damage
²Spring sag
²Abnormal looseness
²Damaged seals.
The following changes indicate a need to inspect and service your
vehicle:
²Changes in steering action.
²Hard steering.
²Excessive free play.
²Unusual sounds when turning or parking.
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If the steering wanders or pulls
This condition can be caused by any of the following conditions:
²Underinflated tire(s) on any wheel(s)
²Front end out of alignment
²Total vehicle out of alignment (i.e. rear axle[s] out of alignment with
front axle)
²Improper adjustment in the steering gear
²Vehicle overloaded or unevenly loaded
²High crosswinds
²High crown in center of road
²Components in steering linkage loose or worn
²Wheel bearings improperly adjusted
²Excessive lash in steering shaft or universal joints
If the vehicle steers hard
Hard steering can be caused by any of the following conditions:
²Underinflated tire(s) on any wheel(s)
²Vehicle overload
²Misalignment of the front tires
²Lack of lubricant in the front spindle bearings or linkage components
²Low oil level in the power steering system
²Broken or loose power steering pump direct drive connection
²Malfunctioning relief valve in power steering gear or steering pump
²Malfunctioning power steering pump
²Restriction in power steering lines
²Improperly set turn stops
²Air 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.
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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).
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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These transmissions have no P (Park) position. Before leaving
the driver's seat, always shift into N (Neutral) and set the
parking brake. Shut the engine off 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.
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 traction. 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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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.
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).
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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
engine should be at idle speed when any shift from N (Neutral) to a
drive range is made.
The N (Neutral) position may also be used during stationary operation of
the Power Take-Off (PTO), if equipped.
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