Gooseneck to Kingpin adapter

Wed, 01 Sep 2021 15:14:15 GMT

go to see Welding Machine for Gooseneck to Kingpin adapter

So since I want to be able to use my 5th wheel hitch to pull my equipment trailer, I bought an adapter. I bought a name brand adapter and now I get to figure out how to fix their quality control. 1 I can use a bur bit and and make the holes line up2 I can just have the adapter be not square with the 5th wheel hitch3 I can find some 4.5' inside diameter pipe and make a 2' sleeve and make new holesI already had to cut 1/4 off the gusset ears to get it to be this closeNot sure which way to go

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Reply:The bottom of that plate has a king pin, right? I'd just pin it and let it ride. You'll hardly notice it after a while and it wont effect the functionality of the adapter.
Reply:Yes the bottom plate has the kingpin
Reply:I would weld the holes shut in the adapter and re drill. Having the plate not square with the trailer would drive me nuts.Trapper
Reply:Having the plate not square with the trailer does drive me nuts
Reply:I feel like an idiot..........but I can't see what's wrong with the plate.  I'm not familiar with these adapters.  Doesn't the sliding tube inside the hitch rotate enough to line up the pin hole with the plate hole where you want it to?My pin just goes in to hold the hitch from rising off the ball, never really considered whether it was square with anything as long as it held the hitch on the ball.I just don't know what I'm looking at.  My pin is at the bottom of the tube, and totally offset to the outside to go underneath the ball


Reply:The holes line up with the outer tube, the issue is that the king pin plate is not welded on square. When pinned it will be not square with the trailer or the 5th wheel hitch
Reply:The issue seems to be that you want the plate square to the road as you travel. I suggest this could be achieved by realigning the trailer axles the required degrees.
Reply:This picture should explain the issue. Since I want the trailer to sit level I will have to cut 3'' off the outer tube and then drill new holes to make the king pin plate square

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Reply:Done!

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Reply:THANKS FOR THE PICS!!!!!!!!!!!!!!!!!!!!!!!!  I really didn't have any idea what was happening.I run 2 different height balls.  A low one for the regular flatbed gooseneck, and a 3" high one for the hay trailer because it tilts to the side about 45*.  I'll take some pics this evening.
Reply:I'm actually thinking you're missing 1/2 of your coupler


Reply:The lower tube, which is a tube inside a tube, should have the pin that goes under the ball.




  This is an extra height ball, but it doesn't matter for your application.  The pin should go under the ball in the curve in the shank.  The coupler should stand fairly proud of the ball.  And there should be another tube that carries the coupler pins, like in the above pictures.
Reply:this is a kingpin so I can use my 5th wheel hitch. I have the stinger if I want to use my ball
Reply:I went out and looked................Do you take the lower tube out, and hard bolt it to the adapter?  I'm just not familiar with these things.
Reply:i'm no damn help at all.  I just don't know about these things
Reply:Aw man, I'm sorry, all I did was booger up the thread
Reply:Sam, it's a 2" kingpin adapter just like a semi. Used mostly for pulling RV trailers. Kind of like this one I built a few years back.

This is the whole rig.

Last edited by 12V71; 07-06-2021 at 07:40 PM.
Reply:Loosen the 2 set bolts and pull the pin, slide the one out and put the other one in and tighten the bolts and put the pin in

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Reply:I understand it now


Reply:Tag tagged gooseneck kingpin adapterI'm not faniliar with gooseneck trailers. I'm just curious as to the differences between a gooseneck and ball or a gooseneck and fifthwheel? Any advantages for one over the other? Nice work!I ask because I recently bought a pickup with a BW ball hitch installed in the bed, a first for me. I use to own semi's so I'm familiar with adapting to non semi trailers as you did, again nice job!Last edited by Stick-man; 07-09-2021 at 10:51 AM."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!

" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:I did it because my one pick up has a 5th wheel hitch in it all the time, and I hate removing it. My other truck has a regular gooseneck. I wanted to be able to pull it with either truck. I finally got my oak wood for the new deck, should have it finished soon

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Last edited by Millwrightdude; 07-09-2021 at 01:18 PM.
Reply:Just got home from the lumber mill with some new oak decking

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Reply:Looks great.the only think that pops out is protecting that trailer light wiring.Miller 211Hypertherm PM 451961 Lincoln Idealarc 250HTP 221  True Wisdom only comes from Pain.
Reply:I put the wiring in the dovetail through the tubing, but couldn’t come up with a real good way of hiding it under the deck.Last edited by Millwrightdude; 07-09-2021 at 10:14 PM.I bought a small utility trailer and they ran a piece of square tube the same size (1-1/2") as the floor boards full length of the trailer to carry the wiring. It is between the boards on the floor. Works okay, but it is new so time will tell.---Meltedmetal
Reply:If the holes were slightly bigger you could probably cut a piece of 5/16 or 3/8 hose … and split it  To protect the wires from chaffing…Miller 211Hypertherm PM 451961 Lincoln Idealarc 250HTP 221  True Wisdom only comes from Pain.
Reply:got 1/2 done yesterday

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Reply:Finished before a small rain shower. Im trying to decide if I want to put used oil on it or not. I don't want a slipper surface or to track oil from my shoes

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Last edited by Millwrightdude; 07-12-2021 at 06:32 PM.
Reply:Linseed oil may be a good choice to help preserve the deck.