Ford F-650 Owner's Manual page 83

Lap belts
The front center and rear center lap belts do not adjust automatically.
WARNING: The lap belt should fit snugly and as low as possible
around the hips, not across the waist.
Insert the tongue into the correct
buckle (the buckle closest to the
direction the tongue is coming
from). To lengthen the belt, turn the
tongue at a right angle to the belt
and pull across your lap until it
reaches the buckle. To tighten the
belt, pull the loose end of the belt
through the tongue until it fits snugly across the hips.
Shorten and fasten the belt when
not in use.
Vehicle sensitive mode
The vehicle sensitive retractor allows free shoulder belt length
adjustment to your movements and locks in response to vehicle
movement. For example, if the driver brakes suddenly or turns a corner
sharply, or the vehicle receives an impact of approximately 5 mph
(8 km/h) or more, the combination safety belts lock to help reduce
forward movement of the driver and passengers.
2012 F-650/750 (f67)
Supplement, 2nd Printing
USA (fus)
Seating and Safety Restraints
83