Look underneath the muffler and see if there is snow coming in past the tie rod boot. I had this problem with my kids. The boot is attatched to a piece of plastic which can come loose allowing snow to build up between the tie rods and the floorpan. Also check the belly of the floorpan. If it is pushed in to far from hitting objects it will rub on the rod coming from the steering shaft to the right spindle, causing a bind. Hope that helps.........