2008 FORD F750 ignition

If brakes do not grip well
•If you have been driving through deep water, gently apply the brakes
several times while the 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. (Air brakes only)
HYDRAULIC BRAKES (IF EQUIPPED)
HydroMax brake booster system
The HydroMax systems receive fluid pressure from the power steering
pump to provide power assist during braking.
The HydroMax booster receives back-up pressure from the reserve
system electric pump whenever the fluid in the power steering system is
not flowing. When the engine is off, the pump will turn on if the brake
pedal is applied, or if the ignition is turned to the ON position.
The sound of the pump operating or fluid flowing through the booster
may be heard; this is a normal characteristic of the system and should be
no reason for concern.
The reserve system provides reduced braking power, so the vehicle
should be operated under these conditions with caution, and only to seek
service repair and remove the vehicle from the roadway.
If braking performance or pedal response becomes very poor, even when
the pedal is strongly applied, this may indicate the presence of air in the
hydraulic system or fluid leakage. Stop the vehicle safely as soon as
possible and seek service immediately.
If the red BRAKE warning lamp in
the instrument cluster remains
illuminated after engine start up,
this indicates a system failure in the
master cylinder of the brake system. Stop the vehicle safely as soon as
possible and seek service immediately.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
92

The parking BRAKE warning lamp
in the instrument cluster illuminates
and will remain illuminated (when
the ignition is turned on) until the
parking brake is released.
Push the palm release lever on the
parking brake handle and push
down as far as possible to release
the brake. Driving with the parking
brake on will cause the brakes to
wear out quickly and reduce fuel
economy.
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.
The parking brake is not
recommended to stop a moving
vehicle. However, if the normal
brakes fail, the parking brake can be
used to stop your vehicle in an
emergency. Since the parking brake only applies retardation to the rear
wheels, the vehicle’s stopping distance will increase greatly and the
handling of your vehicle will be adversely affected.
POWER PARK (AIR-OPERATED PARKING BRAKE) OPTION
(IF EQUIPPED)
This feature uses a brake chamber mounted on the chassis to power a
spring-applied, air-released driveline parking brake. It is controlled by a
yellow, dash-mounted parking brake knob.
P
BRAKE
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
94

Periodically check the air pressure
gauge while driving. Pressure should
range between approximately
100–125 psi (690–862 kPa). The air
compressor governor cut-in and
cut-out pressure settings are preset
at the factory and are not
adjustable.
When air pressure is insufficient
(below 60 psi [414 kPa]), a warning
light illuminates and a buzzer
sounds when the ignition is in the
ON position.
This condition may be caused by excessive brake applications depleting
the system air pressure. If this condition occurs, stop driving the vehicle
until the compressor has fully recharged the air system.
Do not move the vehicle when the air pressure is insufficient
because the brake system may be inoperative.
Select a gear ratio to help slow your vehicle before descending grades.
Supplement with brakes as required to safely slow the vehicle and avoid
overspeeding the engine.
Air chamber stroke indication
Air chamber push rods have orange stroke indicator markers that warn
when the braking system requires adjustment or repair. The orange
stripe is painted on the air chamber push rod at the slack adjuster stroke
dimension which requires service when visible during brake application.
Air brake inspection and adjustment or repairs should be performed by a
qualified service technician in accordance with the instructions in the
service manual.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
98

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.
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 lamp
in the instrument cluster illuminates
and remains illuminated (when the
ignition is turned 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
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
101

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 lamp
The
ABSwarning lamp 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 lamp 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.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
111

•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 Controlsystem. 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 Controloperation,
the traction control light in the
instrument cluster will flash rapidly
and the engine will not “rev-up”
when you push 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 Controlswitch,
located on the instrument panel, is
activated standard Traction
Controlwill change to Off Road
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 Controlcan be selected
by pushing 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 Traction Controlmode. This may
allow excess wheel spin to “dig” the vehicle out and enable a successful
“rocking” maneuver.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
112

Aggressive driving in any road conditions can cause you to lose
control of your vehicle increasing the risk of severe personal
injury or property damage. The occurrence of a Traction Control
event is an indication that at least some of the tires have exceeded
their ability to grip the road; this may lead to an increased risk of loss
of vehicle control, vehicle rollover, personal injury and death. If you
experience a severe road event, SLOW DOWN.
AIR SUSPENSION (IF EQUIPPED)
Note:The vehicle must not be operated without air in the suspension
springs. Operating the vehicle without air in the air suspension springs
will damage the suspension, degrade ride performance and may cause
property damage.
The suspension system automatically adjusts to different loads to
maintain a constant frame height. The system allows for ease of vehicle
loading and provides improved vehicle ride and increased driver comfort.
Air suspension dump switch
The system is controlled by a switch
located on the instrument panel.
The switch will operate only when
the ignition is in the ACC
(Accessory) or IGNITION positions
and the air tanks have sufficient
pressure to fill the air springs. When
the ignition is turned off, the
suspension will remain in whatever
state it was last set.
Note:The suspension will dump air when the ignition is in the ACC or
IGNITION position, but will only fill when the ignition is in the IGNITION
position.
When the upper portion of the switch is pressed air supplied to the air
spring is exhausted, lowering the frame for loading. Pressing the lower
portion of the switch causes air to fill the air springs so the vehicle will
remain at normal ride height.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
113

HAZARD FLASHER
The hazard flasher control is located
on the steering column, just behind
the steering wheel. The hazard
flashers will operate when the
ignition is off.
Push in the flasher control and all
front and rear direction signals will
flash. Press the flasher control again
to turn them off. Use it when your
vehicle is disabled and is creating a
safety hazard for other motorists.
Note:With extended use, the flasher may run down your battery.
FUSING
If electrical components in the vehicle are not working, a fuse may have
blown. Blown fuses are identified by a broken wire within the fuse.
Check the appropriate fuses before replacing any electrical components.
Note:Always replace a fuse with one that has the specified amperage
rating. Using a fuse with a higher amperage rating can cause severe wire
damage and could start a fire.
2008 F-650/750(f67)
Supplement
USA(fus)
Roadside Emergencies
135