Ford 2002 F650 Owner's Manual page 118

Driving
Releasing spring brake manually — F650 SuperCrewzer
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.
Remove the clevis which is attached
to the end of the spring chamber
rod. This can be done by using a
wrench on the flats of the rod to
thread it out of the clevis. There is
sufficient thread length in the clevis
to fully release the parking brake.
Burnish procedure — All except F650 SuperCrewzer
For optimal performance of a new parking brake system/new linings
perform the following procedure:
1. While driving the vehicle at 40 km/h (20 mph) apply the parking brake
(with applicable force to set to approximately 18kg [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.
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