Page 126 of 290
TRAILER AIR SUPPLY AND PARKING BRAKE MODULAR
CONTROLS (IF EQUIPPED)
The trailer air supply valve delivers air to the trailer supply and will
automatically pop out, shutting off the trailer supply, if pressure is
decreased to approximately 35 psi (249 kPa).
The parking brake controls the spring brakes on the tractor. When the
knob is pulled out it causes the trailer supply valve to pop out, applying
both the tractor and trailer parking brakes. The trailer brakes may be
independently released by pushing only the trailer air supply valve in.
Initial charge
With the air system completely discharged, both knobs (1 and 2) will be
out. When the air pressure reaches 70 psi (483 kPa) the trailer air
supply (1 – red knob) may be pushed in and should stay in charging the
trailer air system and releasing the trailer brakes.
TRAILER
AIR SUPPLY
NOT FOR PARKING
TO
TOPULL
SUPPLY
EVACUATE
PUSH
12 12
Driving
126
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
Page 127 of 290
The parking brake (2–yellow knob) can now be pushed in and supply air
to the tractor spring brakes, releasing them.
Normal driving position
With both knobs pushed in, air is then supplied to both trailer and
tractor spring brakes, and all brakes are released.
12
12
Driving
127
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
Page 128 of 290
System park
With both knobs pushed in (normal driving position), the parking brakes
for both the tractor and trailer can be applied by pulling the parking
brake knob (2) out, exhausting air from the tractor spring brakes,
simultaneously causing the trailer air supply valve to pop out, applying
the trailer brakes.
Trailer charge
If both knobs are out, and you want to recharge the trailer while leaving
the tractor spring brakes applied, the trailer air supply (1) can be
pushed in to recharge the trailer air supply line. This mode may also be
used to park a combination vehicle with tractor spring brakes.
12
12
12
12 12
Driving
128
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
Page 129 of 290

Automatic application
If both knobs are pushed in and the brake system air pressure is reduced
to approximately 35 psi (249 kPa), the trailer air supply (1) knob will
automatically pop out applying the emergency or parking brakes on the
trailer. If the trailer air supply (1) knob is manually held in and the air
pressure is reduced to approximately 30 psi (207 kPa), a tripper piston
within the valve will move, exhausting the trailer air supply, applying the
trailer brakes. Further reduction of air pressure, while holding the trailer
air supply knob in, will cause the parking brake knob to pop out at 25 psi
(172 kPa).
Actuation of trailer park (emergency) or tractor bobtail position
To actuate the trailer brakes only, pull out the trailer air supply knob (1).
The trailer brakes are now applied whether emergency or spring brakes
are used on the trailer.
This mode is also used when the tractor or truck with trailer is used
during bobtail operation.
12
1
2
Driving
129
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
Page 130 of 290

ANTI-LOCK BRAKE SYSTEM (ABS)
A noise from the hydraulic pump motor and pulsation in the pedal may
be observed during ABS braking events. Pedal pulsation coupled with
noise while braking under panic conditions or on loose gravel, bumps,
wet or snowy roads is normal and indicates proper functioning of the
vehicle’s ABS. If the vehicle has continuous vibration or shudder in the
steering wheel while braking, the vehicle should be inspected by a
qualified service technician.
The ABS operates by detecting the
onset of wheel lockup during brake
applications and compensating for
this tendency. The wheels are
prevented from locking even when
the brakes are firmly applied. The
accompanying illustration depicts
the advantage of an ABS-equipped
vehicle (on bottom) to a non-ABS
equipped vehicle (on top) during hard braking with loss of front braking
traction.
ABS warning light
The
ABSwarning light in the instrument cluster momentarily illuminates
when the ignition is turned on and the engine is off. If the light does not
illuminate momentarily at start up, remains on after the vehicle reaches
5–10 mph (8–16 km/h), or continues to flash, the ABS needs to be
serviced.
With the ABS light on, the anti-lock brake system is disabled and normal
braking is still effective unless the brake warning light also remains
illuminated. (If your parking brake warning light illuminates, have your
vehicle serviced immediately.)
Using ABS
•In an emergency or when maximum efficiency from the ABS is
required, apply continuous full force on the brake. The ABS will be
activated immediately, thus allowing you to retain full steering control
of your vehicle and, providing there is sufficient space, will enable you
to avoid obstacles and bring the vehicle to a controlled stop.
•The ABS does not decrease the time necessary to apply the brakes or
always reduce stopping distance. Always leave enough room between
your vehicle and the vehicle in front of you to stop.
Driving
130
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
Page 131 of 290

•We recommend that you familiarize yourself with this braking
technique. However, avoid taking any unnecessary risks.
TRACTION CONTROL (IF EQUIPPED)
Your vehicle may be equipped with a traction control system. This
system helps you maintain the stability and steerability of your vehicle,
especially on slippery road surfaces such as snow- or ice-covered roads
and gravel roads, by reducing engine power and/or selectively applying
the rear brakes. The system will allow your vehicle to make better use of
available traction in these conditions.
Note:The traction control system will not apply the brakes when the
vehicle speed is above 25 mph (40 km/h).
During traction control operation,
the traction control light in the
instrument cluster will flash rapidly
and the engine will not “rev-up”
when you press further on the
accelerator. This is normal system
behavior and should be no reason
for concern. If the traction control
light does not flash during a traction control event or stays illuminated,
the system is not functioning properly, take your vehicle to your dealer
for service.
When the traction control switch,
located on the instrument panel, is
activated standard traction control
will change to Off Road or
Mud/Snow traction mode, the
traction control light will be
illuminated and flash slowly. If a
traction event occurs, in either
mode the traction control light will
flash rapidly. The standard traction
control can be selected by pressing
the traction control switch again or will be automatically selected at next
ignition cycle.
If you should become stuck in snow or ice or on a very slippery road
surface, try switching to the Off Road or Mud/Snow traction control
mode. This may allow excess wheel spin to “dig” the vehicle out and
enable a successful “rocking” maneuver.
MUD/SNOW
TRACTION
Driving
131
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
Page 133 of 290

Tractor-trailer connections
WARNING:To reduce the risk of personal injury, use extreme
caution when making brake and light connections. Inclement
weather and accumulated road contamination deposits on handhold
and stepping surfaces require extra care to avoid slip and falls. Provide
adequate lighting of working areas.
WARNING:Do not climb on the back of the tractor unless it
has been provided with a deck plate and handholds. Use a
three-point stance when climbing up and down from a deck plate. Do
not jump from the vehicle. Whenever possible, make all connections
while standing on the ground.
Connecting and disconnecting a trailer with air suspension and air
suspension dump switch (if equipped)
When connecting to a trailer:
•Press the lower portion of the dump switch and air will exhaust from
the air suspension system.
•After making the connection to the trailer, press the upper portion of
the dump switch, then raise the landing gear.
When disconnecting the trailer:
•Lower the landing gear, then press the lower portion of the dump
switch.
•Disconnect the brake hoses, trailer-side and rear light connectors,
then pull the release lever on the fifth wheel.
The upper portion of the dump switch must be pressed before operating
with a trailer or operating in the bobtail mode.
Suspension conversions
It is not recommended, or approved, that suspension conversions be
performed. However, it is understood that, on occasion, aftermarket
add-on suspensions are installed by others on the truck chassis which
allow operator control for weight transfer from other axles (i.e., air lift
axles).
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.
Driving
133
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)
Page 134 of 290

AUTOMATIC TRANSMISSION OPERATION (IF EQUIPPED)
Main transmission, auxiliary transmission, transfer case and power
take-off (PTO) control shift patterns can be found on a placard or decal
on the driver’s sun visor, on the instrument panel or on the shift control
itself.
The main transmission control is used to select the various gear ratios or
speeds of the transmission. Selecting D (Direct Drive), does not change
the transmission gear ratio, but is used where the gear ratios in the main
transmission are adequate to handle the vehicle operation.
If the transmission fails to shift properly, check the inline 10A fuse
located in the battery cables above the battery.
WARNING:Hold the brake pedal down while you move the
gearshift lever between positions. If you don’t hold the brake
pedal down, your vehicle may move unexpectedly and cause property
damage, personal injury or death.
Allison 2200 with park pawl feature
Note:For Allison automatic transmission-equipped vehicles, also refer to
the separateAllison Transmission Operator’s Manual.
A parking pawl effectively grounds the transmission’s output shaft
preventing rotation of the driveline. If the vehicle is stationary, selecting
the P (Park) position places the transmission in neutral and engages the
parking pawl (always use the parking brake, also).
Note:If the P (Park) position is selected when the vehicle is in motion,
the parking pawl mechanism will ratchet andNOThold the truck.
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 P (Park). 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.
Driving
134
2011 F-650/750(f67)
Supplement, 2nd Printing
USA(fus)