Ford 2009 Expedition Owner's Manual page 280

Tires, Wheels and Loading
Weight distributing hitch
When hooking up a trailer using a load equalizing hitch, always use the
following procedure:
1. Park the unloaded vehicle on a level surface. With the ignition in the
ON position and all doors closed, allow the vehicle to stand (without
passengers) for several minutes so that it can level.
2. Turn the air suspension (if equipped) control to off.
3. Measure the height of a reference point on the front and rear bumpers
at the center of the vehicle.
4. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within a
After proper adjustment, the rear bumper should be no higher than in
Step 3.
5. Turn the air suspension (if equipped) control to on.
WARNING: Do not adjust a weight distributing hitch to any
position where the rear bumper of the vehicle is higher than it
was before attaching the trailer. Doing so will defeat the function of
the weight distributing hitch, which may cause unpredictable handling,
and could result in serious personal injury.
Safety chains
Always connect the trailer's safety chains to the frame or hook retainers
of the vehicle hitch. To connect the trailer's safety chains, cross the
chains under the trailer tongue and allow slack for turning corners.
If you use a rental trailer, follow the instructions that the rental agency
gives to you.
Do not attach safety chains to the bumper.
Trailer brakes
Electric brakes and manual, automatic or surge-type trailer brakes are
safe if installed properly and adjusted to the manufacturer's
specifications. The trailer brakes must meet local and Federal
regulations.
WARNING: Do not connect a trailer's hydraulic brake system
directly to your vehicle's brake system. Your vehicle may not
have enough braking power and your chances of having a collision
greatly increase.
280
2009 Expedition (exd)
Owners Guide, 1st Printing
USA (fus)
1 ⁄ " (13 mm) of the reference point.
2