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Exhaust brake operating characteristics
When you remove your feet from both the accelerator and clutch pedals
and the exhaust brake switch is in the ON position, the exhaust brake is
activated. The following conditions should exist if the brake is operating
properly:
•A slight change in the sound of the engine when the exhaust brake is
activated.
•Exhaust smoke appears normal.
•Engine temperature remains in the normal operating range.
•Road speed usually decreases when the exhaust brake is applied
during a descent, except when the vehicle is carrying a heavy load or
the grade is extremely steep. In these instances, you may need to
apply the service brakes occasionally.
•During a descent, the tachometer usually shows a drop in RPM
depending on the grade and the vehicle load.
•Do not expect a retarding effect similar to sudden hard application of
the service brakes. The exhaust brake retards the vehicle with a
smooth braking effect.
•Depending on the grade and vehicle load, you may or may not feel the
retarding force acting against your body when the brake is applied.
The brake’s retarding force is actually preventing the vehicle from
going much faster.
Make sure the exhaust brake is turned off before shutting off the engine.
Installing an exhaust or auxiliary brake should never allow the
engine to exceed maximum governed speeds under any
conditions.
Air brake reservoir draining
Failure to drain air brake reservoirs can result in a reduction or
loss of braking ability due to fluid accumulation in the reservoir
and/or possible freeze-up during cold weather.
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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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![FORD F650 2003 10.G Owners Manual •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 c FORD F650 2003 10.G Owners Manual •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 c](/manual-img/11/5069/w960_5069-130.png)
•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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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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