2009 FORD F750 brakes

Air brake reservoir draining
WARNING: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 psi/kPa, by
opening the draincock at the ends
of the tanks (where accessible.
Pull-chains are used when the
drains are undercab or otherwise
inaccessible). 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.
Parking brake
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 R
(Reverse) for vehicles equipped with manual transmission, N (Neutral)
for vehicles with automatic transmission (except Allison 2200
transmission) or P (Park) (Allison 2200 transmission).
If the service brakes should fail to operate while the vehicle is in motion,
you can make an emergency stop with the parking brake. Since the
parking brake only applies stopping power to the rear wheels, the
vehicle’s stopping distance will greatly increase and the handling of the
vehicle will be adversely affected. Repairs should be made immediately
to an inoperative air brake system circuit.
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
108

Parking brake control (knob)
Pull the yellow parking brake knob
out to apply the parking brake. Push
the knob in to release the parking
brake.
WARNING: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, N (Neutral) for
automatic transmission (except
Allison 2200 transmission) or P
(Park) (Allison 2200
transmission). Use of wheel
chocks is also recommended in
hilly or off-road usage.
The parking BRAKE warning light in
the instrument cluster illuminates
and remains illuminated (when the
ignition is turned to ON) until the
parking brake is released.
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.
P
BRAKE
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
109

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.
EXHAUST BRAKE (IF EQUIPPED)
Note:The exhaust brake is
intended to help control vehicle
speed; it is not a vehicle stopping
device.
An exhaust brake is an optional
auxiliary braking system that assists,
but does not replace, the primary
service brake system. An on-off
switch on the instrument panel, in
combination with the accelerator
and clutch pedal switches, 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
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
111

Operation
Push the rocker switch up to turn
the exhaust brake on. The switch
will illuminate in the ON position.
Push the switch down to turn the
brake off.
Starting engine
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 temperatures.
Driving downhill
While approaching a steep grade, make sure that the exhaust brake
switch is in the ON position. The exhaust brake actuates as soon as you
remove your foot from the accelerator pedal. 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 would to ascend the hill.
Before descending a hill or steep grade always select the proper gear. If
the transmission is taken out of gear while descending it is possible that
you will not be able to select another gear because of maximum RPM
being governed.
Note:Maximum exhaust brake performance is related to the type of
transmission your vehicle is equipped with.
Note:Manual transmissions should be downshifted to the lowest gear
possible, without exceeding the maximum RPM limit of the engine. This
will maximize the exhaust brake’s retarding effect.
Note:Exhaust brakes will operate effectively with automatic
transmission, but performance will vary with engine speed and the gear
selected by the transmission.
Make sure the engine speed does not exceed the maximum allowable
engine RPM. Exceeding the maximum allowable engine RPM will 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.
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
112

Note:Engine speed has a major influence of retarding performance.
When engine speed is maintained at the maximum allowable level, the
exhaust brake will operate at peak performance.
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.
Exhaust brake operating characteristics
When you remove your feet from both the accelerator and clutch pedals
and the exhaust brake switch is in the on position, the exhaust brake is
activated. The following conditions should exist if the brake is operating
properly:
•A slight change in the sound of the engine when the exhaust brake is
activated.
•Engine temperature remains in the normal operating range.
•Road speed usually decreases when the exhaust brake is applied
during a descent, except when the vehicle is carrying a heavy load or
the grade is extremely steep. In these instances, you may need to
apply the service brakes occasionally.
•During a descent, the tachometer usually shows a drop in RPM
depending on the grade and the vehicle load.
•Do not expect a retarding effect similar to sudden hard application of
the service brakes. The exhaust brake retards the vehicle with a
smooth braking effect.
•Depending on the grade and vehicle load, you may or may not feel the
retarding force acting against your body when the brake is applied.
The brake’s retarding force is actually preventing the vehicle from
going much faster.
•Engine speed has a major effect on retarding performance, with higher
engine speeds permitting greater retarding ability.
•Engine brake performance is closely related to the type of
transmission your vehicle is equipped with. Downshifting of manual
transmission to the lowest gear possible, without exceeding the
maximum engine RPM limit, will maximize retarding performance.
Exhaust brakes will operate effectively with automatic transmissions,
but performance will vary with engine speed and the gear selected by
the transmission.
Make sure the exhaust brake is turned off before shutting off the engine.
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
113

Note:Installing an exhaust or auxiliary brake does not necessarily
protect the engine from exceeding maximum governed speed. The
primary brakes should be used to make sure the engine never exceeds
maximum governed speed under any conditions.
TRAILER BRAKE HAND CONTROL (IF EQUIPPED)
The hand control, located on the
right-hand side of the instrument
panel, is used to apply the trailer
service brakes which are
independent of the truck or tractor
service brakes.
WARNING:The hand
control should never be
used to apply the brakes when the
tractor and trailer are parked
unattended. Air may leak from the
system and the vehicle could
possibly move, resulting in
possible property damage,
personal injury or death.
The hand control operates a valve that provides gradual control of air
pressure applied; when the valve is only partially applied, the trailer
brakes can be overridden by pressing fully on the brake pedal.
To apply the trailer brakes using the hand control, move the lever
downward. The further the lever is pushed downward, the greater the air
pressure is applied to the brakes. The lever will remain in place until
manually moved.
To release the trailer brakes, move the lever upward completely.
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
114

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
TOP
U
L
L
SUPPLY
EVACUATE
PUSH
12 12
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
115

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
2009 F-650/750(f67)
Supplement
USA(fus)
Driving
116