2008 FORD F750 wheel

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

If the parking brake is applied due to low air pressure, immediate service
is required to the parking brake system.
Parking brake warning system
If the park brake light blinks and a chime sounds when pulling the yellow
control knob out, this indicates the parking brake is not functioning
properly; seek service for the parking brake immediately.
The light will blink and the chime will sound until the yellow control
knob is pushed in or approximately eight minutes have passed. If the
yellow control knob is pulled out again, the light will blink and the chime
will sound as a reminder that immediate service is required to the
parking brake system.
Releasing spring manually
Do not attempt to disassemble the parking brake chamber under
any circumstances. The high spring load may cause serious
injury.
If air pressure is released from the spring brake chamber the power
spring applies the brake and, unless air pressure can be re-established,
the spring brake must be released as follows in order to move the
vehicle.
Block the wheels to help prevent the vehicle from moving.
Unexpected and possibly sudden vehicle movement may occur if
these precautions are not taken.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
96

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
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.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
100

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

Releasing spring brake manually
Do not attempt to disassemble the parking brake chamber under
any circumstances. The high spring load may cause serious
injury if the chamber clamps are removed.
If air pressure is released from the spring brake chamber the power
spring applies the brake and, unless air pressure can be re-established,
the spring brake must be released as follows in order to move the
vehicle.
Block the wheels to help prevent the vehicle from moving.
Unexpected and possibly sudden vehicle movement may occur if
these precautions are not taken.
Impact wrenches should not be used as they may damage the piston and
prevent proper caging of the spring. Do not apply more than 50 lb. ft.
(68 N•m) torque to the release bolt nut.
1. Remove the stud tool and nut
from the carrying pocket on the
brake chamber assembly.
2. Remove the access plug from the
end of the spring chamber.
3. Insert the release stud through
the opening in the chamber and into
the spring pressure plate.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
102

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

Tractor-trailer connections
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.
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
When connecting to a trailer:
•Press the lower portion of the switch and air will exhaust from the air
suspension system.
•After making the connection to the trailer, press the upper portion of
the switch, then raise the landing gear.
When disconnecting the trailer:
•Lower the landing gear, then press the lower portion of the 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 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).
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.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
114