Use a double line (with snatch block = $50 from northern tool) winch method to pull the machine slowly onto a trailer, this puts the winch into a slower & stronger pull. Or you can simply call on a reputable towing service. I've heard of some guys lightly oiling down the steel deck on a trailer to ease the dragging a little bit. It really sounds absurd, but as long as it works & doesn't destroy anything, you should be ok.