Towing a 2003 F150 4X4 Behind a Class A - Will it work?

If your 4x4 is "automatic", then you will need to look at options like a driveshaft disconnect. If you have a selector knob on the dash that lets you choose 4x2 or 4x4 there is a kit available from Ford that lets you put the transfer case into neutral (between 4H and 4L). I have that kit installed on my 2002 Explorer Sport Trac. It requires a computer update so has to be done by the dealer. I forget what I cost, but I think it was in the neighborhood of $500.