Hi. My new F450 pickup truck has arrived, and I backed it under my (also new-to-me) 2005 34' fifth wheel RV for the first time yesterday as I begin to make plans for hitches, etc. My general plan is to install an under-the-bed gooseneck hitch on the truck, and a 5th wheel to gooseneck adapter on the trailer. The truck has a long bed and DRW.
Whether I choose to go with a gooseneck or fifth wheel hitch, I have to be concerned about clearance between the rear bumper of the truck and the trailer. With the kingpin centered over the rear axle, there is only 13 inches between the outside corners of the rear bumper and the trailer. I expect that once the hitch is installed the kingpin will be just forward of the rear axle by a few inches, and bumper/trailer distance would be 10". I'm certain that isn't enough distance. What is the minimum bumper/trailer distance rule to eliminate clearance problems?
To solve the problem, I could install a longer pin box, or an offset gooseneck ball, or an offset version of the 5th wheel to gooseneck adapter. Any thoughts? Thanks.
I would measure the distance from the anticipated pivot point in the box, to the corner of the bumper at the edge of the vehicle. Then I would use this distance to measure from the trailer pin to the front of the lower overhang. directly back, then add some inches for insurance.
I would put a piece of electrical tape on the center of the bed, 1" forward of the rear axle, where the fifth wheel pivot point would normally be located.
This is your target for the center of the hitch to end up. The trailer needs to stretch to this point, and the truck needs to be at least 4" ahead of the fifth wheel during a 45 degree turn, so back the truck under the fifth wheel at a 45 degree angle until it is nearly touching the storage compartment door.
You will know how far the trailer hitch needs to go forward, to reach the tape on the pickup bed. Then get the right adapter to move the center of the hitch to where it is required to make a 180 degree turn while backing up.
However I might still suggest that a fifth wheel hitch will have a little more stability in crosswinds, and suggest that type of hitch be installed. Yet it is your truck, your choice.
Try this; with a tape, measure from the king pin stright back to the trailer add 4 or 5 inches this will be the distance needed from the center of hitch jaws on a 5th wheel or center of gooseneck ball to the conner of your truck/bumper for clearance needed. I think that I have about 4" on mine. Hope this helps. John
Next thing to do is to forget the Goose Neck Adapter. It will mostl likely void you frma warranty on the trailer.
In addition, it looks like an engineering disaster waiting to happen.
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