From my limited experience with my truck in the snow, the rear wheels don't hook up very good at all. But, when you go 4x4 the front hooks up great and eliminates the loose rear end. I would think it would be the same on a dually, 4x4 working great and 2x4 not great at all. Just my opinions, I would say if you will be towing that fifth regularly, then get the dually and don't worry about the snow.