FORD 2012 Expedition v.2 - Manual (Page 194)

Once the child safety seat has been installed using either the safety belt,
the lower anchors of the LATCH system, or both, you can attach the top
tether strap.
If you install a child seat with rigid LATCH attachments, and have
attached the top tether strap to the proper top tether anchor, do not
tighten the tether strap enough to lift the child seat off the vehicle seat
cushion when the child is seated in it. Keep the tether strap just snug
without lifting the front of the child seat. Keeping the child seat just
touching the vehicle seat gives the best protection in a severe crash.
Perform the following steps to install a child safety seat with tether
anchors:
Second row seating positions
1. For center seating positions, route the child safety seat tether strap
over the back of the seat.
For outboard seating positions, route the tether strap under the head
restraint and between the head restraint posts. If the top of the safety
seat hits the head restraint, recline the seatback slightly to obtain proper
fit.
2. Locate the correct anchor for the selected seating position.
• Second row outboard seating
positions
• Second row center seating
position (if equipped)
Seating and Safety Restraints
194
2012 Expedition (exd)
Owners Guide, 3rd Printing
USA (fus)