FORD F750 2015 13.G Owners Manual

Position 1
•Provides maximum engine braking.
•Allows upshifts by moving gearshift lever.
•The transmission does not downshift into position1at high speeds; it
downshifts to a lower gear and then shifts into position1when your
vehicle reaches slower speeds.
Forced Downshifts
•Allowed in positionD.
•Press the accelerator to the floor.
•Allows transmission to select an appropriate gear.
Allison 2200 with Parking Pawl Feature
Note:Also, see the separateAllison Transmission Operator’s Manual.
WARNING:Always set the parking brake fully. Do not use the
gearshift in place of the parking brake.
WARNING: To avoid sudden, unexpected vehicle movement
and possible personal injury or death:
1. Bring the vehicle to a complete stop.
2. Shift the transmission into positionP.Slowly lift your foot from the
brake pedal to engage the transmission parking pawl mechanism.
3. Apply the parking brake and make sure it is holding properly. Do not
rely solely on the parking mechanism of the transmission.
4. Turn the engine off when you leave the vehicle.Never leave the
vehicle unattended when the engine is running.
A parking pawl effectively grounds the transmission’s output shaft
preventing rotation of the driveline. If your vehicle is stationary, selecting
positionPplaces the transmission in neutral and engages the parking
pawl. Always use the parking brake when parking your vehicle.
Note:If you select positionPwhen your vehicle is moving, the parking
pawl mechanism ratchets and does not hold the truck.
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Allison 2500
WARNING: To avoid sudden, unexpected vehicle movement
and possible personal injury or death:
1. Bring the vehicle to a complete stop.
2. Shift the transmission into positionN.
3. Apply the parking brake and make sure it is holding properly.
4. Turn the engine off when you leave the vehicle.Never leave the
vehicle unattended when the engine is running.
This transmission is available with a column-mounted gearshift lever. The
instrument cluster displays the gear positions.
Allison 3000
Note:For more information about this transmission, see the separate
Allison 3000 Series Operator’s Manual.
The Allison 3000 series offers two shift modes: Performance and
Economy.
Performance mode gives the best all-around transmission operation. The
transmission defaults to this mode when you start the engine. Pressing
MODE on the shifter switches to Economy mode and illuminates the
Mode ON lamp.
Economy mode provides operation at lower engine RPM while
maintaining adequate performance.
If the engine speed is above idle when a gear is selected using the
shifter, the vehicle does not move; the shifter must be moved to re-select
a gear after the engine speed returns to idle.
Torque Lock
If you park your vehicle on an incline without properly engaging position
P(by shifting into positionPbefore applying the parking brake), the
weight of the vehicle may generate an excessive amount of torque on the
parking pawl. This makes it difficult to shift the transmission out of
positionP.Hold the brake pedal down while shifting out of positionP,
then release the parking brake.
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Allison 3000 Series Push-Button Shifter
To shift to Reverse or Drive:
1. Press the brake pedal.
2. Press R or D on the shifter.
3. Release the brake pedal.
To select a higher range when in Drive,
press the up arrow button.
To select a lower range when in Drive,
press the down arrow button.
To place the transmission in Neutral, press
N.
Allison 3000 Prognostics
This transmission is equipped with the Allison Prognostics feature that
can alert the driver to needed transmission maintenance and
transmission fluid and filter life. See the separate Allison transmission
manual for complete details.
POWER TAKE-OFF (PTO) OPERATION (IF EQUIPPED)
A PTO unit allows the transmission to power auxiliary equipment to run
devices such as snowplows, aerial lifts, tow truck lifts, cement mixers or
dump trucks.
Vehicles Equipped with an Allison Automatic Transmission (Except
3000 Series)
You can operate the PTO while your vehicle is standing or moving. To
engage the PTO, apply the brakes and shift to any gear other than
positionN,then engage the PTO.
If the gear teeth not meshing properly prevent engagement, release the
brakes and allow your vehicle to creep slightly or shift the selector to
positionNand then back into gear. Never engage the PTO by clashing
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the gear teeth. This may damage the PTO unit and the transmission PTO
drive gear teeth, resulting in further damage to the transmission and
PTO.
PTO Operation with Vehicle Stationary
WARNING:When the PTO is operated with the vehicle
stationary, the transmission must be placed in positionNwith the
parking brake set. If the transmission is not in positionNand 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 injury and/or property damage.
Stop your vehicle, idle the engine and set the parking brake. Make sure
the gear selector is in any forward drive range, and then engage the
PTO. After engaging the PTO, move the range selector to positionN.
Increase the engine speed until reaching the desired PTO operation
speed. To disengage the PTO after operation with your vehicle standing,
release the throttle, allow the drive equipment to come to a stop, and
then disengage the PTO.
PTO Operation while Vehicle Is Moving
After engaging the PTO for driven vehicle operation, shift to the desired
range and drive your vehicle. The speed of the PTO, during this period
of operation, always maintains direct relation to vehicle speed. PTO
speed decreases in relation to vehicle (transmission output) speed as
shifts to a higher gear occur. When operating the PTO while your vehicle
is moving, the PTO may be disengaged whenever it is no longer required.
When there is no load on the PTO gear, you can pull it out of
engagement.
Vehicles Equipped with an Allison 3000 Series Automatic
Transmission
The PTO drive gear is engine-driven and provides direct engine power.
You can operate the PTO when your 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 transmits
power to the PTO.
Vehicles Equipped with a Manual Transmission
Transmission-mounted PTO units are available for local installation on
your vehicle. See yourBody Builder’s Layout Bookfor restrictions on
use and installation of PTO units.
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To engage the PTO unit, stop your vehicle, place the transmission in
positionN.Press the clutch, and allow the gears to stop rotating, and
then engage the PTO unit. You can also select the PTO with the
transmission in gear as long as the clutch is pressed.
When operating the PTO with your vehicle stationary, first set the
parking brake (chock the wheels if your vehicle is on a hill or another
uneven surface).
REAR AXLES
Gross Axle Weight
WARNING:Exceeding these ratings by overloading can cause
component failure resulting in property damage, personal injury
or death.
Your truck has gross axle weight, gross vehicle weight and gross
combination weight ratings. Do not exceed these ratings.
Locking or Limited-Slip Differentials
WARNING:If both wheels are not raised off the ground, the one
wheel that is not raised may pull the vehicle off its support,
possibly resulting in personal injury
If your vehicle is equipped with a locking or limited-slip differential, note
the following:
•Power is transmitted to the opposite wheel should one of the wheels
begin to slip.
•Both wheels must be raised off the ground should it be necessary to
operate one wheel with your vehicle stationary.
Driver-controlled Differential Lock
Note:Never use the differential lock at vehicle speeds above 25 mph
(40 km/h).
Some drive axles have a driver-controlled differential lock. The
differential lock can lock or unlock the differential when your vehicle is
moving or stopped. When extra traction is required, the differential lock
provides full power to both axles.
When you lock the differential, your vehicle’s turning radius increases
(under-steer).
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You can lock and unlock the differential when your vehicle is moving at a
constant speed of less than 25 mph (40 km/h) and while the wheels are
not slipping. Do not lock the differential when your vehicle is traveling
down steep grades and traction is minimal.
The differential lock and differential lock light automatically disengage at
speeds above 25 mph (40 km/h). The differential lock remains off until
either you restart your vehicle or you turn the differential lock switch off
then back on.
Turn the engine off and raise all drive wheels of the locker differential
axle in order to prevent your vehicle from moving when servicing the
wheels, tires or brakes. Axles equipped with a NoSPIN Detroit Locker
differential deliver power to both wheels even when only one wheel is on
the ground.
WARNING:Failure to raise all drive wheels with this type of
differential could cause the vehicle to move unexpectedly,
resulting in property damage, personal injury or death.
Take care to avoid sudden accelerations when both drive wheels are on a
slippery surface.
WARNING:Sudden accelerations on slippery surfaces could
cause the wheels to spin, the vehicle to turn sideways on a
crowned road surface or in a turn, possibly resulting in loss of vehicle
control and personal injury.
Fluid Temperature
Axle operating temperatures normally do not exceed 100°F (38°C). If
the operating temperature exceeds 230°F (110°C), the rate of axle
lubrication oxidation increases and shortens the life of the lubricant and
seals, requiring axle lubrication changes to become more frequent to
preserve the axle. Do not consistently run extreme pressure (EP)
lubricants above 230°F (110°C).
Axle Conversions
WARNING:When operating a loaded vehicle, the driver must
keep all adjustable axles on the ground at all times, supporting
their share of the vehicle’s load. Failure to do so can overload other
axles, tires, wheels, springs, steering components, brakes and frames,
resulting in early component failure, loss of vehicle control, possible
property damage and personal injury.
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We do not recommend, or approve, performing axle conversions.
However, we understand that, on occasion, others install aftermarket
add-on axles on the truck chassis that allow operator control for weight
transfer from other axles (such as air lift axles).
TWO-SPEED REAR AXLE (IF EQUIPPED)
WARNING:Never shift a two-speed axle when descending a
steep grade as this may cause loss of vehicle control and result in
personal injury.
Note:Do not shift between ranges when the speed control is on.
A two-speed rear axle allows the
driver to select a low range for
greater pulling power and a high
range for greater road speed and
fuel economy. You can also use
these ranges to provide extra steps
between transmission shifts when
driving on steep grades or fuel
economy may be factors.
Axle Shifting with a Manual Transmission
To downshift, select the next lower gear, release and press the
accelerator pedal rapidly, or while holding the accelerator pedal down,
release and engage the clutch rapidly.Note:Use the clutch method
when driving at slower speeds.
To upshift, keep the accelerator pedal down, select the next higher gear,
release the accelerator and pause until the axle upshifts.Note:
De-clutch for smoother axle upshifts when driving at slower speeds.
Axle Shifting with an Automatic Transmission
Note:You cannot split-shift with an automatic transmission. In addition,
downshifting above 40 mph (64 km/h) may result in transmission or axle
damage.
Note:Do not shift the axle to LOW with your vehicle is moving.
Use LOW when you drive a fully loaded vehicle on a severe grade or in
congested traffic. Press the upper portion of the switch.
Use HIGH for all normal driving conditions with a lightly loaded or
partially loaded vehicle. Press the lower portion of the switch.
2SPD
LOW
HIGH
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To shift the axle from LOW to HIGH with your vehicle stopped, place the
transmission in positionN,then press the lower part of the switch.
To shift the axle from LOW to HIGH with your vehicle moving, accelerate
to approximately 35 mph (56 km/h), press the lower part of the switch
while the transmission is in positionN,then release and apply the
accelerator.
To shift the axle from HIGH to LOW with the vehicle stopped, place the
transmission in positionN,then press the upper part of the switch.
Split-shifting (Combined Axle and Transmission Shift) (Manual
Transmission Only)
To downshift the axle to a slower ratio and shift the transmission, shift
the transmission and move the switch to the lower ratio before the
clutch is re-engaged.
To upshift the axle and shift the transmission, move the switch to a
faster ratio and make the transmission shift in the usual manner.
Split-shift Sequence
Ratio combination 1234567891011
Transmission gear 1st 1st 2nd 2nd 3rd 3rd 4th 4th 5th 6th 6th
Axle range LO HI LO HI LO HI LO HI LO LO HI
Ratio Extender Use
Low end:You can use a two-speed axle as a ratio-extender when
split-shifting is not necessary. For low end use, just shift the axle into
LOW to start out, and shift to HIGH when you longer need the extra
torque.
Transmission (5-speed) 1st 1st 2nd 3rd 4th 5th 6th
Two-speed axle Axle low Axle high
High end:To use the two-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
Two-speed axle Low for gradeability Axle high
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GENERAL INFORMATION
All standard equipment brakes self-adjusting. Automatic adjustment,
when required, occurs whenever you apply and release the brakes during
forward or reverse operation.
Note:Occasional brake noise is normal. If a metal-to-metal, continuous
grinding or continuous squeal sound is present, this may indicate worn
brake linings. Have them inspected by an authorized dealer. If your
vehicle has continuous vibration or shudder in the steering wheel while
braking, an authorized dealer should inspect the vehicle.
Know the required stopping distances for all driving conditions you may
encounter. For longer brake lining life, take full advantage of engine
braking power when coming to a stop.
WARNING:Do not drive with your foot resting on the brake
pedal. This results in abnormally high brake temperatures,
excessive lining wear and increased stopping distances.
Before descending a long or steep hill, shift to a lower gear and avoid
continuous application of the brakes. Normally, choose the same gear to
descend the hill that you use to ascend the hill.
WARNING:Continuous application of the brakes causes the
brakes to overheat, resulting in a temporary loss of braking.
See theInstrument Clusterchapter for information on the
brake system warning light.
Wet brakes result in reduced braking efficiency. Gently press the brake
pedal a few times when driving from a car wash or standing water to dry
the brakes.
If Brakes Do Not Grip Well
•If you have been driving through deep water, gently apply the brakes
several times while your vehicle is moving slowly.
•Let the brakes cool if you have been using them excessively, as in
mountain driving or after several fast, high-speed stops.
•Check brake adjustment.
•Check brake linings for excessive wear.
•Check system air pressure on vehicles equipped with air brakes.
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Anti-lock Brake System (ABS)
This system helps you maintain steering control during emergency stops
by keeping the brakes from locking.
The ABS lamp momentarily illuminates when you switch on the
ignition. If the light does not illuminate during start-up, if it
remains on or flashes, the ABS may not be working and
requires servicing.
If the ABS is disabled, normal braking is still effective. If the
brake warning lamp illuminates, have your brake system
serviced immediately.
If you connect a PLC trailer with the ignition on, the trailer
ABS light also illuminates. If the light fails to illuminate, if it
remains on after you start the vehicle or continues to flash,
have the system serviced immediately.
FULL POWER BRAKE SYSTEM
WARNING:If the red BRAKE warning lamp in the instrument
cluster remains illuminated after engine start up, this indicates a
system failure in the Full Power Brake System. Stop the vehicle safely
as soon as possible and seek service immediately.
This system incorporates standard braking, an anti-lock braking system
(ABS) and optional Power Park Brake into one fully integrated hydraulic
brake system. With the Full Power Brake System, braking energy is
stored, similar to an air brake system, resulting in faster response times
and shorter stopping distances. This is accomplished using motor and
pump assemblies that pressurize the system by pumping brake fluid into
accumulators. This is similar to the air compressor of an air brake system
pressurizing the air tanks. The system includes a master cylinder that
provides the normal pedal feel and transfers the pedal force, via brake
fluid, to the main components of the system.
Note:The motor and pumps run momentarily with the ignition switch in
the on or run position, or in the off position with the brake pedal
pressed.
Note:During normal driving, you may hear the pump and motors
replenishing the accumulators. This is a normal function of the system.
AIR BRAKES
After starting the engine, give the air compressor time to build up the air
pressure to 60 psi (414 kPa) before moving your vehicle.
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