Ford F series Owner's Manual page 117

3. Pull the belt out of the retractor as far as it
will go and untwist the belt or remove the
object that is jamming the belt. Let the belt
retract.
4. Then, pull the belt out and let it retract
several times to make sure that the belt
works properly.
Procedure to Correct a Twisted Safety
Shoulder Belt at the "D" Ring (if so
equipped) Front and/or Rear Outboard
Seating Positions.
NOTE: The restraint system shown in the
following figures may be different than
the restraint system in your vehicle.
However, use these figures and this
procedure to correct a twisted safety
shoulder belt at any outboard seating
position that has a "D" ring.
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