
Driving through water
If driving through deep or standing water is unavoidable, proceed very
slowly especially if the depth is not known. Never drive through water
that is higher than the bottom of the hubs (for trucks) or the bottom of
the wheel rims (for cars). Traction or brake capability may be limited
and your vehicle may stall. Water may also enter your engine’s air intake
and severely damage your engine.
Once through the water, always dry the brakes by moving your vehicle
slowly while applying light pressure on the brake pedal. Wet brakes do
not stop the vehicle as quickly as dry brakes.Driving through deep
water where the transmission vent tube is submerged may allow
water into the transmission and cause internal transmission
damage.
HYDRAULIC BRAKES (IF EQUIPPED)
Your service brakes are self-adjusting. Refer to theGeneral
Maintenance Informationfor scheduled maintenance.
Occasional brake noise is normal and often does not indicate a performance
concern with the vehicle’s brake system. In normal operation, automotive
brake systems may emit occasional or intermittent squeal or groan noises
when the brakes are applied. Such noises are usually heard during the first
few brake applications in the morning; however, they may be heard at any
time while braking and can be aggravated by environmental conditions
such as cold, heat, moisture, road dust, salt or mud. If a“metal-to-metal,”
“continuous grinding”or“continuous squeal”sound is present while
braking, the brake linings may be worn-out and should be inspected by a
qualified service technician.
If you are driving down a long or steep hill, shift to a lower gear.
Do not apply your brakes continuously, as they may overheat
and become less effective.
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.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
91

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.
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.
Burnish procedure (hydraulic brakes with park lever only)
For optimal performance of a new parking brake system/new linings
perform the following procedure:
1. While driving the vehicle at 16 km/h (10 mph) apply the parking brake
(with applicable force to set to approximately 18 kg [40 lbs]). Allow the
vehicle to come to a complete stop.
2. Release the parking brake, drive 16.8 km (1.5 miles) to cool the
brakes.
3. Repeat steps 1 through 2 ten times.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
94

Loosen the jam nut (1) and un-thread the adjustment rod (2) from the
chamber to reduce tension on the cable (3). Continue to un-thread the
adjustment rod all the way and remove it from the chamber. The nut and
shaft are metric.
AIR BRAKES (IF EQUIPPED)
Foot service brakes
Air brakes are operated by a
standard dash-mounted foot pedal.
All standard equipment brakes are
designed to be self-adjusting.
Automatic adjustment, when
required, occurs whenever the
brakes are applied and released
during forward or reverse operation.
Know the required stopping
distances for all driving conditions
that may be encountered. For longer brake lining life, take full advantage
of engine braking power when coming to a stop.
Before descending a long or steep hill, shift to a lower gear and avoid
continuous application of the brakes.
Do not drive with your foot resting on the brake pedal. This will
result in abnormally high brake temperatures, excessive lining
wear and increased stopping distances.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
97

Continuous application of the brakes will cause the brakes to
overheat, resulting in a temporary loss of braking.
Occasional or intermittent brake squeal or groan may result from
environmental conditions such as cold, hot, wet, snow, salt, mud, etc.
This condition will not affect braking effectiveness. The brakes should be
checked only if squeal occurs continuously with every application.
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 brake reservoir draining
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 kPa/psi, 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.
Air brakes
After starting the engine, give the air compressor time to build up the air
pressure to 414 kPa (60 psi) before moving the vehicle.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
98

Do not drive or continue to drive if the low air pressure buzzer
is sounding or the brake warning light is lit. These warnings
indicate that air pressure is not to normal operating level. Continued
use of the vehicle could result in loss of braking ability.
Avoid repeated light application of the brake pedal. This will
deplete air pressure faster and could result in loss of braking
capability.
Periodically check the air pressure
gauge while driving. Pressure should
range between approximately 724 to
930 kPa (105-135 psi). 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 414 kPa [60 psi]), 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 in this condition 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 stripes that alert the
operator when the braking system requires adjustment or repair. The
orange stripe is painted on the air chamber push rod at the slack
adjuster readjustment stroke dimension.
0 30 12090 60
150AIR
PRESSUREPSI
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
99

Air brake inspection and adjustment should be performed by a qualified
service technician in accordance with the instructions in the service
manual.
Cam brakes - automatic slack adjusters
Standard air brakes (cam) are
equipped with automatic brake
adjusters. Automatic adjustment
occurs during brake applications.
Inspect brakes for proper
adjustment at the intervals listed in
the vehicle Service Maintenance
Guide.
Emergency air brake
All vehicles are equipped with a dual brake system. In the unlikely event
of a failure of one system, the second system will function for emergency
stopping. These systems are all controlled by the brake pedal in the
same manner as for normal stops.
Do not continue to operate the vehicle with a failure of one of
the systems. Take the vehicle to your dealer for service
immediately.
Parking brake
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 R (Reverse) for vehicles equipped with manual
transmission, N (Neutral) for vehicles with automatic transmission
(except Allison 2400 transmission) or P (Park) (Allison 2400
transmission).
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
100

Unexpected and possible sudden vehicle movement may occur if
these precautions are not taken.
If the service brakes should fail to operate while the vehicle is in motion,
you can make an emergency stop with the parking brake. The stopping
distance, however, will be much greater than normal. Repairs should be
made immediately to an inoperative air brake system circuit.
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 2400 transmission) or P
(Park) (Allison 2400
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.PARKING
BRAKE
PULL TO
RELEASE
APPLY
PUSH TO
P
BRAKE
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
101

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.
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 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 68 Nm (50
lb-ft) 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.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
102