According to Remco:
"
Vehicle can be flat towed with Lube Pump Kit. Vehicle cannot be flat towed from Manufacturer as is.
The center disconnect must be locked out by capping off one of the front-axle vacuum motor lines for the Manual Transfer Case vehicles. See dealer for assistance.
Ford 6-Speed Transmission, 6R80 Transmission, vehicles with a Manual Shift transfer case can be flat towed. Electronic Shift-On-the Fly 4WD transfer cases cannot be flat towed without a Lube Pump Kit. For vehicles with Manual transfer case, shift transmission into NEUTRAL and shift manual transfer case into NEUTRAL before flat towing."
"