Scott,a 5th wheel is pretty much what the name implies. It's a flat plate with a V cut into it with a locking device that a pin on the trailer slides into. The weight of the trailer is spread over the 5th wheel plate. A goose neck connection is just a trailer ball mounted in-between the wheels in the middle of the bed. Many times folks will call a 5th wheel,a gooseneck,I'm not sure if this is right or wrong. The advantage of a 5th wheel is that the trailer weight is spread over more area and they are easier to hook up to because the V provides a bigger target. Disadvantage is that you have a big plate in your bed which can be harder to remove than a gooseneck ball and take up more room if you want to use your bed,some newer 5th wheel plates do remove more easily though. I use a gooseneck to haul 25k loads with no problems,it's up to the individual.
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95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(Play truck)95 3500,5 speed,Driftwood,Banks&Phscotty,34,000 GCVW apple and tractor hauler(work truck)