2015 FORD F750 Transmission

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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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

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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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

HINTS ON DRIVING WITH ANTI-LOCK BRAKES
When the system is operating, the brake pedal pulses and may travel
further. Maintain pressure on the brake pedal. You may also hear a noise
from the system. This is normal.
The ABS does not eliminate the dangers inherent when:
•You drive too closely to the vehicle in front of you.
•Your vehicle is hydroplaning.
•You take corners too fast.
•The road surface is poor.
EXHAUST BRAKE (IF EQUIPPED)
WARNING:The exhaust brake is not recommended for use on
slippery or low traction road surfaces. Under these conditions a
loss of vehicle control could occur.
Note:Installing an exhaust or auxiliary brake does not necessarily
protect the engine from exceeding maximum governed speed. Use the
primary brakes to make sure the engine never exceeds maximum
governed speed under any conditions.
Note:Before starting the engine, make sure that the exhaust brake
switch is in the off position. Do not turn the exhaust brake on until the
engine has reached normal operating temperature.
Note:Maximum exhaust brake performance relates to the type of
transmission your vehicle has.
Note:Engine speed has a major influence of retarding performance.
When engine speed is stays at the maximum allowable level, the exhaust
brake operates at peak performance.
Note:Manual transmissions should be downshifted to the lowest gear
possible, without exceeding the maximum RPM limit of the engine. This
maximizes the exhaust brake’s retarding effect.
Note:Exhaust brakes operate effectively with automatic transmissions,
but performance varies with engine speed and the gear selected by the
transmission.
An exhaust brake is an auxiliary braking system that assists, but does
not replace, the primary service brake system. It helps control vehicle
speed; it is not a vehicle-stopping device.
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

A switch on the instrument panel,
in combination with the accelerator
and clutch pedal, allows the
operator to make maximum use of
the exhaust brake in the following
conditions:
•Off-highway driving
•Mountain driving
•Heavy traffic
•High-speed highway driving.
To switch the brake on, push the switch up. Push the switch down to
turn it off.
While approaching a steep grade, make sure that the exhaust brake
switch is in the on position. The exhaust brake begins working as soon as
you remove your foot from the accelerator pedal.
Before descending a hill or steep grade, always select the proper gear. If
you take the transmission out of gear while descending, it is possible that
you cannot select another gear because of maximum governed RPM.
Make sure the engine speed does not exceed the maximum allowable
engine RPM. Exceeding the maximum allowable engine RPM can result
in damage to the engine. Apply the service brakes to reduce the engine
RPM or make a slower descent by using a lower gear.
While going down the grade, use a low enough gear to descend safely
with a minimum application of the service brakes. As a general guideline,
use the same gear as you use to ascend the hill.
Exhaust Brake Operating Characteristics
The exhaust brake turns on when you remove your feet from both the
accelerator and clutch pedals and the exhaust brake switch is in the on
position. The following conditions exist if the brake is operating properly:
•A slight change in engine sound when the exhaust brake turns on.
•A smooth braking effect. Do not expect a retarding effect similar to
sudden, hard application of the service brakes.
•The retarding force possibly felt acting against your body during
brake application (depending on the grade and vehicle load). This
force is actually preventing the vehicle from going much faster.
•Engine temperature remaining in the normal operating range.
•The tachometer showing a drop in engine RPM (depending on grade
and vehicle load) during a descent.
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Actuation of Trailer Park (Emergency) or Tractor Bobtail Position
To actuate the trailer brakes only, pull out the trailer air supply knob
(A). This applies the trailer brakes whether the trailer uses emergency
or spring brakes.
You can also use this mode when the tractor or truck with trailer is used
during bobtail operation.
PARKING BRAKE
Hydraulic Brakes
WARNING:Do not use the gearshift selector in place of the
parking brake. Always set the parking brake fully AND make sure
the gearshift selector is in positionRfor vehicles equipped with a
manual transmission or positionP (if equipped)orNfor vehicles
equipped with an automatic transmission. Use of wheel chocks is also
recommended in hilly or off-road usage. Unexpected and possible
sudden vehicle movement may occur if these precautions are not taken.
WARNING:If the parking brake is fully released but the parking
brake warning lamp remains illuminated, the brakes may not be
working properly. See your dealer or a qualified service technician.
Apply the parking brake whenever the vehicle is parked. To set the
parking brake, pull the handle up until it snaps into the locked position.
When the parking brake is out of adjustment, seek service immediately.
The parking brake warning lamp in the instrument cluster
illuminates, and remains illuminated (when you switch on the
ignition), until you release the parking brake.
B
A
P
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Note:Read and understand the following steps and perform them
whenever you prepare to drive the vehicle.
Note:The parking brake does not disengage unless sufficient system air
pressure is available.
If your vehicle is equipped with a dash-mounted push button (Allison
3000 Series) or steering column-mounted (Allison 2200 and 2500) gear
selector:
1. Press and hold the service brake pedal while the engine is running.
2. Select the appropriate drive gear.
3. Push and hold the yellow, dash-mounted parking brake knob until the
parking brake light turns off, then release.
If your vehicle is equipped with a manual transmission:
1. Press and hold the service brake pedal while the engine is running.
2. Press and hold the clutch pedal.
3. Select the appropriate drive gear.
4. Push and hold the yellow, dash-mounted parking brake knob until the
parking brake light turns off, then release.
Parking Brake Light Illumination Due to Low Air Pressure
If the air pressure becomes too low at any time during vehicle operation,
the parking brake may apply and the parking brake light turns on.
If the parking brake applies due to low air pressure, immediate service is
required to the parking brake system.
Parking Brake Warning System
If the parking brake light blinks and a tone sounds when pulling the
yellow control knob out, this indicates the parking brake is not
functioning properly. Seek service for the parking brake immediately.
With the ignition key not in the run position:
•A tone sounds if the parking brake remains released (or in an
unknown state). The tone stops in approximately eight minutes or
until the parking brake is applied. Seek service for the parking brake
immediately.
Diesel engines:Parking brake light operation (the light only works
when the ignition key is in the run position):
•On:Parking brake applied.
•Off:Parking brake released and no faults or malfunctions.
•Blink and tone:Parking brake released (or in an unknown state)
and faults or malfunctions exist.
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Air Brakes
WARNING:Do not use the gearshift selector in place of the
parking brake; unexpected and possible sudden vehicle
movement may occur if these precautions are not taken. Always set the
parking brake fully AND make sure the gearshift selector is in position
Rfor vehicles equipped with manual transmission or positionN(except
Allison 2200 transmission) orP(Allison 2200 transmission) for vehicles
with automatic transmission.
If the service brakes should fail to operate while your vehicle is moving,
you can make an emergency stop with the parking brake. Since the
parking brake only applies stopping power to the rear wheels, your
vehicle’s stopping distance greatly increases and the handling of your
vehicle is adversely affected. Make repairs immediately to an inoperative
air brake system circuit.
WARNING:This control is used for parking only. Do not leave
the vehicle unattended after setting the parking brake without
placing the transmission inpositionRfor vehicles equipped with manual
transmission or positionN(except Allison 2200 transmission) orP
(Allison 2200 transmission) for vehicles with automatic transmission.
Use of wheel chocks is also recommended in hilly or off-road usage.
Pull the yellow parking brake knob
out to apply the parking brake.
Push the knob in to release the
parking brake.
The parking brake light illuminates and remains illuminated
(when you switch the ignition to the on position) until you
release the parking brake.
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 lets you recharge
P
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

OPERATING YOUR VEHICLE
General Information
•Start the vehicle moving by using the highest gear speed in the
transmission that lets the engine easily start the load without slipping
the clutch.
•Accelerate smoothly and evenly. Rapid acceleration increases fuel
consumption without increasing engine performance.
•When approaching a hill, press the accelerator smoothly to start the
incline at full power, and then shift down as needed to maintain
vehicle speed.
•When going down a hill, or long steep grades, prevent overspeeding
of the engine. Normally, choose the same gear to descend the hill that
you use to ascend the hill. The engine governor has no control over
engine speed when it is being pushed by a loaded vehicle.
•Do not operate in a gear that permits an engine speed more than the
maximum governed speed or high-idle RPM (no load).
•Always shift to a lower gear at high altitudes to prevent engine
smoking.
Backing Up
WARNING:All vehicles have blind spots. To reduce the risk of
severe injury or property damage, never move your vehicle to the
side or rear or change lanes without being sure your way is clear on
both sides and to your rear.
WARNING:To reduce the risk of the possibility of personal
injury while backing up the vehicle, always be sure your vehicle’s
path is clear.
Before backing up your vehicle, be sure you can do so safely. If anything
behind the cab limits your view, do not rely on mirrors alone to make
sure that your intended path is clear. If other people are in the vicinity,
have someone standing well behind your vehicle and outside of your
intended path (visible through an exterior mirror) guide you as you back
up.
Although OSHA or some governmental regulations may require the use
of an electrical or mechanical back up alarm to warn bystanders, such an
alarm does not guarantee that the intended path is clear. When in doubt,
get out of your vehicle and visually check the intended path is clear.
Back up slowly as to allow others time to move, if necessary.
Driving Aids159
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)