This is from the 2016 Ford manual
Park the loaded vehicle, without the trailer, on a level surface.
Measure the height to the top of your vehicle's front wheel opening on the fender. This is H1.
Attach the loaded trailer to your vehicle without the weight-distributing bars connected.
Measure the height to the top of your vehicle's front wheel opening on the fender a second time. This is H2.
Install and adjust the tension in the weight-distributing bars so that the height of your vehicle's front wheel opening on the fender is approximately a quarter the way down from H2, toward H1.
Check that the trailer is level or slightly nose down toward your vehicle. If not, adjust the ball height accordingly and repeat Steps 2-6.
