Air Brakes
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 position
Rfor vehicles equipped with manual transmission or positionN(except
Allison 2200 transmission) orP(Allison 2200 transmission) for vehicles
with automatic transmission.
If the service brakes should fail to operate while your vehicle is moving,
you can make an emergency stop with the parking brake. Since the
parking brake only applies stopping power to the rear wheels, your
vehicle’s stopping distance greatly increases and the handling of your
vehicle is adversely affected. Make repairs immediately to an inoperative
air brake system circuit.
WARNING:This control is used for parking only. Do not leave
the vehicle unattended after setting the parking brake without
placing the transmission inpositionRfor vehicles equipped with manual
transmission or positionN(except Allison 2200 transmission) orP
(Allison 2200 transmission) for vehicles with automatic transmission.
Use of wheel chocks is also recommended in hilly or off-road usage.
Pull the yellow parking brake knob
out to apply the parking brake.
Push the knob in to release the
parking brake.
The parking brake light illuminates and remains illuminated
(when you switch the ignition to the on position) until you
release the parking brake.
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 lets you recharge
P
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)
the system with air from an outside source, releasing the spring-actuated
parking brakes. Your vehicle is now ready to tow in an emergency.
You can only use an outside air source if the protected system is in
operating condition. If you cannot restore air pressure in the protected
air system, you must release the spring-actuated brakes manually.
Releasing Spring Manually
WARNING: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 you release air pressure from the spring brake chamber, the power
spring applies the brake and, unless air pressure can be re-established,
you must release the spring brake as follows in order to move your
vehicle.
WARNING:Block the wheels to help prevent the vehicle from
moving.
WARNING:Unexpected and possibly sudden vehicle movement
may occur if these precautions are not taken.
Do not use impact wrenches as they may damage the piston and prevent
proper caging of the spring. Do not apply more than 50 foot-pounds
(68 newton-meters) 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.
Brakes153
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)