FORD F750 2000 10.G Owners Manual
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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.
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.
PARKING
BRAKE
PULL TO
RELEASE
APPLY
PUSH TO
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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.
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Trailer brake
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.
Do not use the trailer brake manual control lever for parking.
Trailer air supply control (MV-3) (Tractor package)
The MV-3 control module is a two-button, push-pull control valve housed
in a single body which includes a dual circuit supply valve and a check
valve.
Operation
During initial charge, with the system completely discharged, both
buttons are out.
When system pressure reaches
448 kPa (65 psi), the red control
(trailer supply) may be pushed in
and should stay in, charging the
trailer system and releasing the
trailer brakes.
The yellow control (parking brake)
may now be pushed in, which will
supply air to the tractor spring
brakes, releasing them.
TRAILER
AIR SUPPLY
NOT FOR PARKING
PULL
TO
TOEVACUATE
PUSH
SUPPLY
PARKING
BRAKE
PULL
TOAPPLY
PUSH
TORELEASE
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Normal operating position
With both controls pushed in, air is supplied to the trailer and to the
tractor spring brakes; all brakes are released.
Actuation of trailer parking or emergency brakes
To actuate the trailer brakes only,
pull out the red control (trailer air
supply), exhausting the trailer
supply line. The trailer brakes are
now applied either by air emergency
or spring brakes, depending on the
type of trailer system. This mode
would be used to uncouple from the
trailer during bob-tail operation.
System park
With both controls in for normal run modes, the parking brakes on both
tractor and trailer may be actuated by pulling the yellow control (parking
brake) out, which exhausts the air from the tractor spring brakes and
simultaneously causes the red control (trailer supply) to pop out,
applying the trailer brakes. This complies with federal regulations stating
one control must apply all the parking brakes on the vehicle.
Trailer charge
If both controls are out when parking the combination vehicle and it is
desired to recharge the trailer (leaving the tractor spring brakes
applied), the trailer air supply control may be pushed in, repressurizing
the trailer supply line. This mode could also be used to park a
combination vehicle with air actuated emergency brakes on the trailer to
provide demonstrated parking capability with tractor spring brakes only.
Automatic application
With both controls in (in the normal run configuration), if the supply
pressure to the push-pull valves is reduced to approximately 240 to
310 kPa (35-45 psi), the red control (trailer supply valve) must pop out,
applying the emergency or parking brakes on the trailer. If the red
control is held in manually and the pressure decreases to approximately
172 to 240 kPa (25-35 psi), a tripper piston within the MV-3 valve will
move upward. This will exhaust the trailer supply, causing the required
TRAILER
AIR SUPPLY
NOT FOR PARKING
PULL
TO
TOEVACUATE
PUSH
SUPPLY
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non-override feature. The yellow control (parking brake) will pop out at
approximately 138 to 207 kPa (20-30 psi).
Reservoir selection
The number one service reservoir will at all times be selected as the
primary supply source for the MV-3. This is accomplished automatically
by the function of the dual circuit supply valve contained in the body of
the MV-3. Only in the event of a pressure drop of more than 207 kPa
(30 psi) below that of the number two service reservoir will the dual
circuit supply valve shuttle and establish the front service reservoir as
the supply.
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.
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.
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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
•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
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•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
DRIVING WITH A MANUAL TRANSMISSION, IF EQUIPPED
Continued use of a damaged or worn clutch, prolonged clutch
slippage or downshifting at excessive speeds can result in a
failure of the engine, transmission or clutch components.
To avoid premature clutch wear and failure, do not drive with
your foot resting on the clutch pedal or use it to hold the vehicle
at a standstill on an upgrade as when waiting for a traffic light.
Manual transmission shift patterns
are displayed on the shift lever
knob.
Study this information carefully before you drive the vehicle even though
you may be familiar with similar units. Do not attempt to drive the
vehicle without knowing the exact shift pattern of the transmission.
Consult your authorized dealer if any questions exist as to the shifting
instructions posted in your vehicle.
Do not coast the vehicle with the clutch pedal depressed or with
the transmission in neutral. This practice could result in loss of
vehicle control.
R 1 3 5
4
6 2
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Always use a gear ratio low enough to allow the engine to operate above
the minimum engine operation speed range. Do not lug the engine. When
more power is required, shift to a lower gear and accelerate the engine
near the governed speed.
Driving hints
The following driving hints are provided as a brief, general guide in
operating the different manual transmissions used in your vehicle.
•Always use the lowest gear to start the vehicle.
•Do not slam or jerk lever into gear.
•When shifting into 1 (First) or R (Reverse) with vehicle standing still,
quickly release and depress the clutch pedal (if necessary to complete
gear engagement).
Operating the Eaton FS-4205A and FS-5205A 5–speed
transmissions
The 5-speed transmission is
equipped with five forward gears
and one reverse. All forwards gears
are synchronized. The shift pattern
is embossed on the gear shift knob.
Do not shift the transmission into R (Reverse) while the vehicle is
moving as this could damage the transmission.
To go forward
With the engine idling, depress the
clutch pedal and shift into 1 (First).
Engage the clutch while pressing
the accelerator to start forward.
Operate the clutch and upshift as
required by driving conditions.
R 2 4
3 5 1
R 2 4
3 5
1
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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.
Operating the Eaton FS-5306A and FS–6306A 6-speed
transmissions
These 6-speed transmissions are
equipped with six forward gears and
one reverse. The 2nd, 3rd, 4th, 5th
and 6th gears are synchronized. The
shift pattern is embossed on the
gear shift knob.
Do not shift the transmission into 1 (First) or R (Reverse) while the
vehicle is moving as this could damage the transmission.
To go forward
With the engine idling, depress the
clutch pedal and shift into 1 (First).
Engage the clutch while pressing
the accelerator to start forward.
Operate the clutch and upshift as
required by driving conditions.
R 2 4
3 5 1
R 1 3 5
4
6 2
R 1 3 5
4
6 2
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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.
Operating the Spicer ES52-7B and ES066-7B 7-speed
transmissions
These 7-speed transmissions are
equipped with seven forward gears
and one reverse. The 2nd, 3rd, 4th,
5th, 6th and 7th gears are
synchronized. The shift pattern is
embossed on the gear shift knob.
Do not shift the transmission into 1 (First) or R (Reverse) while the
vehicle is moving as this could damage the transmission.
To go forward
With the engine idling, depress the
clutch pedal and shift into 1 (First).
Engage the clutch while pressing
the accelerator to start forward.
Operate the clutch and upshift as
required by driving conditions.
R 1 3 5
4
6 2
2 4 6
3 5 71 R
2 4 6
3 5 7
1 R
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