Ford F-650 2001 Owner's Manual page 111

Driving
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.
Parking brake — F650 SuperCrewzer only
Pull the yellow parking brake knob
out to apply the parking brake. Push
the knob in to release the parking
brake.
PARKING
BRAKE
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