FORD 2013 F-550 v.1 - Manual (Page 264)

Recreational Towing
Note: Put your climate control system in recirculated air mode to
prevent exhaust fumes from entering the vehicle. See the Climate
Control chapter.
Follow these guidelines if you have a need for recreational (RV) towing.
An example of recreational towing would be towing your vehicle behind
a motorhome. These guidelines are designed to ensure that your
transmission is not damaged.
Drivetrain
configuration
Requirements for neutral towing
4WD with manual-shift
transfer case Transmission in N (Neutral); transfer case in N
(Neutral); hublocks set to FREE.
*
2WD or 4WD with
electronic-shift
transfer case (ESOF) Do not tow your vehicle with any wheels on
the ground, as vehicle or transmission damage
may occur. It is recommended to tow your
vehicle with all four (4) wheels off the ground,
such as when using a car-hauling trailer.
Otherwise, no recreational towing is permitted.
* Always make sure that both hub locks are set to the same position.
Towing 263
2013 F-250/350/450/550 (f23)
Owners Guide gf, 1st Printing
USA (fus)