Ford 2006 F-350 Owner's Manual page 166

Tires, Wheels and Loading
Improper removal/installation of the driveshaft can cause
transmission fluid loss, damage to the driveshaft and internal
transmission components.
4x4 with manual shift transfer case:
• Place the transfer case in N (Neutral).
• Front hub locks are in the FREE position.
4x4 electronic shift transfer case vehicles with automatic
transmissions:
Regarding recreational towing or having your vehicle towed, 4x4 vehicles
with electronic shift on the fly cannot be towed with any wheels on the
ground unless the rear driveshaft is removed and the front hub locks are
in free mode (with the exception of moving it as a disabled vehicle off
the road out of traffic). The hub locks can be set to free mode at any
time by turning them from AUTO to LOCK and back to AUTO at least
two times. Always make sure that both hub locks are set to the same
position.
166
2006 F-250/350/450/550 (f23)
Owners Guide (post-2002-fmt)
USA (fus)