Ford 2009 F-250 Owner's Manual page 211

WARNING: Airbags can kill or injure a child in a child seat. If
you must use a forward-facing child seat in the front seat, move
seat all the way back.
WARNING: Rear facing child seats should NEVER be placed in
front of an active airbag.
2. Slide the tongue up the webbing.
3. While holding both shoulder and
lap portions next to the tongue,
route the tongue and webbing
through the child seat according to
the child seat manufacturer's
instructions. Be sure that the belt
webbing is not twisted.
2009 F-250/350/450/550 (f23)
Owners Guide, 2nd Printing
USA (fus)
Seating and Safety Restraints
211