2002 FORD F750 torque

Using the engine block heater (if equipped)
An engine block heater warms the engine coolant, which improves
starting, warms up the engine faster and allows the heater-defroster
system to respond quickly. Use of an engine block heater is strongly
recommended if you live in a region where temperatures reach -23É C
(-10É F) or below.
For best results, plug the heater in at least three hours before starting
the vehicle. Using the heater for longer than three hours will not harm
the engine, so the heater can be plugged in the night before starting the
vehicle.
To prevent electrical shock, do not use your heater with
ungrounded electrical systems or two-pronged (cheater)
adapters.
Operating the engine
Do not operate the engine at full throttle below peak torque engine
speed (RPM) for more than one minute at a time (peak torque RPM
varies from 1200-1500 RPM depending on engine rated speed).
Monitor the oil pressure and coolant
temperature gauges frequently.
If the gauges indicate any reading is
not in the normal operating range,
stop your vehicle as soon as
possible, shut the engine off and
check the appropriate fluid level. If
an overheating condition starts to
occur, release the throttle pressure
or shift the transmission into a
lower gear, or both, until the
temperature returns to normal operating range.
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Continuous operation with low
coolant temperature, below 60ÉC
(140ÉF) or high coolant temperature
100ÉC (212ÉF) can damage the
engine.
Most failures give some kind of early
warning. Look and listen for changes
in performance, sound or engine
appearance that can indicate service
or engine repair is needed. Some
changes to look and/or listen for:
²Engine misfires
²Loss of power
²Sudden changes in engine operating temperature or oil pressure
²Excessive smoke
²Fuel, oil or coolant leaks
²Vibration
²Increased oil or fuel consumption
Excessive full throttle operation below peak torque RPM will shorten
engine life to overhaul and can cause serious engine damage. Operation
of the engine below peak torque RPM can occur during gear shifting due
to difference of gear ratios.
Engine shutdown system (if equipped)
This system is designed to help prevent engine damage that could result
from operating the engine during a prolonged period of low engine oil
pressure, high engine coolant temperature or low coolant level. If any of
these conditions occur, a warning light will illuminate and a chime will
sound warning the operator that the engine will shutdown in 30 seconds.
This is to allow time for the operator to move the vehicle off the road. If
additional time is required, the engine can be restarted and run each
time for approximately 30 seconds.
Do not attempt to use this restarting feature to drive the vehicle, serious
engine damage could result.
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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.
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.
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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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engaged by clashing the gear teeth. This may damage the PTO unit and
the transmission PTO drive gear teeth. This could result in further
damage to the transmission and PTO.
PTO operation with vehicle stationary
To operate the power take-off, stop the vehicle, idle the engine and set
the parking brake. Make sure the gear selector is in any forward drive
range, then engage the PTO. After the PTO is engaged for stationary
vehicle operation, move the range selector to N (Neutral). Increase the
engine speed until the desired power take-off operation speed is
obtained. To disengage the PTO after operation with the vehicle
standing, release the throttle, allow the drive equipment to come to a
stop, and then disengage the PTO.
When the PTO is operated with the vehicle stationary, the
transmission must be placed in N (Neutral). If the transmission
is not in N (Neutral) and is equipped with a remote throttle control, an
increase in engine speed can overpower the parking brake and cause
the vehicle to move, possibly resulting in personal and/or property
damage.
PTO operation while vehicle is moving
After the PTO is engaged for driven vehicle operation, shift to the
desired range and drive the vehicle. The speed of the PTO, during this
period of operation, will always maintain direct relation to vehicle speed.
PTO speed will decrease in relation to vehicle (transmission output)
speed as shifts to a higher gear occur. When operating the PTO while the
vehicle is moving, the PTO may be disengaged whenever it is no longer
required. When there is no load on the PTO gear, it can be pulled out of
engagement.
Power take-off (PTO) operation with an Allison automatic
transmission (MD applications)
The PTO drive gear is engine driven and provides direct engine power.
The PTO can be operated when the vehicle is either stationary or
moving.
The PTO gear is in constant mesh with the drive gear in the torque
converter housing. A friction clutch or constant drive is used to transmit
power to the PTO.
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BACKING UP
To avoid the possibility of personal injury while backing the
vehicle, always be sure your vehicle's path is clear.
Before backing your vehicle, be sure you can do so safely. If anything
behind the cab limits your view, do not rely on mirrors alone to assure
that your intended path is clear. If other persons are in the vicinity, have
someone standing well behind the vehicle and outside your intended
path - visible through an exterior mirror - guide you as you back up.
Although OSHA or other governmental regulations may require use of an
electrical or mechanical back-up alarm to warn bystanders, such an
alarm does not assure that the intended path is clear.
An electrical back-up alarm, if installed, is connected to the back-up
lamp circuit.
TWO SPEED REAR AXLE
General Information
A 2±speed axle allows the vehicle operator to selectLow Rangefor good
starting and pulling power. The operator may also selectHigh Range
which allows for greater road speed and economy.
High or Low Range can also be used to provide additional steps between
transmission gear ratios when either gradeability or economy are a
driving factor.
Axle upshift
Brake Torque
In any type of shift, you must brake torque your vehicle. This is done by
releasing the accelerator, because torque creates a binding action on the
sliding clutch gear. This binding must be relieved in order for the shift to
take place.
Axle upshifts transmission gears may be abrupt, causing the truck to
jerk. Using the clutch with the accelerator will smooth the shift.
In order to shift from LOW to HIGH,
²Pull the axle shift accelerator up.
²Release the accelerator.
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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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10. Reset the air filter restriction indicator.
11. Inspect the air induction system for loose fitting, damaged or missing
components and repair as necessary.
SERVICING YOUR WHEELS AND TIRES
Wheel assembly
Your vehicle is fitted with hub
piloted wheels and two-element
swiveling lug nuts (20 & 22 mm).
Do not use taper type wheels or ball
seat wheel nuts.
²Do not paint the mating face of the hub/drum.
²Do not paint the two-element swiveling lug nuts or wheel stud.
²Do not allow an excessive thickness of paint to build between the disc
wheel mounting surfaces.
²Do not install disc wheels where the paint has not fully cured.
²At wheel changes, ensure mounting faces are clean and free of rust,
dirt and excess paint.
If fasteners are needed, use only Ford recommended replacement parts.
²To maintain the desired
torque/tension relation between
nut body and flange, it is
necessary to use clean engine oil
meeting Ford specification
WSS-M2C153-G between nut body and flange. Lubricate the nut body
and flange any time a wheel is removed.
Maintenance and Specifications
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