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Buyers Products 2" Forged SAE Trailer King Pin with 5/16" Bolster Plate - Weld On
Buyers Products

Buyers Products 2" Forged SAE Trailer King Pin with 5/16" Bolster Plate - Weld On

Part Number: 337KP20031
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$74.75
Retail:$137.13
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5th Wheel Pin Box
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Buyers Products 5th Wheel Pin Box - 337KP20031

  • King Pin Only
  • Buyers Products


Buyers Products 2" Forged SAE weldable Trailer King Pin provides strength and reliability in coupling your fifth wheel. Forged from AISI 8630 steel and heat treated to maintain a hardness of 302-363 BHN and 150,000 PSI in ultimate strength. The King Pin has a 3/10" thick bolster plate and a 3" bolster plate hole thickness.


  • Forged from AISI 8630 Steel
  • Heat treated to create and maintain a hardness of 302-363 BHN
  • 150,000 P.S.I. in ultimate strength
  • Bolster plate thickness: 3/10"
  • Bolster plate hole thickness: 3"
  • Forged steel construction
  • Plain finish
  • Made in the USA

KP20031 Buyers Products 2 Inch Forged SAE Trailer King Pins With 5/16 Inch Bolster Plate - Weld On





Video of Buyers Products 2" Forged SAE Trailer King Pin with 5/16" Bolster Plate - Weld On

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Buyers Products Fifth Wheel King Pin - Universal King Pin - 337KP20031 Review

Speaker 1: Today we're taking a look at a two-inch forged SAE trailer King Pin. This trailer King Pin provides strength and reliability in coupling your fifth wheel. It's forged from AISI 8630 steel, and heat treated to maintain a hardness of 302-363 BHN, and 150,000 PSI in ultimate strength. Now the King Pin features a five-sixteenth inch thick bolster plate, so the five-sixteenth inch measurement is measured from the bottom of this plate here to the top of that lip, so that portion right there is five-sixteenths of an inch.Again, we're looking at a forged steel construction with a plain finish. This is a weld-on installation. The overall diameter measuring edge to edge going in this direction, that gives us a measurement of eight inches.

From very bottom to very top, so I'm going to place that flat edge on there, then I'm going to measure up to it. That's four and one-quarter inches, and then from the bottom to the bottom of the top plate, so measuring this space right here, that measures three and five-eighths inches.Now this portion, that has a diameter of 2 and 13/16 inches. This section right here has a diameter of two inches, and at the very base it has a diameter of three inches. Again, nice durable forged steel construction, and the product's made in the USA.That's going to do it for today's look at the two-inch forged SAE trailer King Pin.


Customer Reviews

Buyers Products 2" Forged SAE Trailer King Pin with 5/16" Bolster Plate - Weld On - 337KP20031

Average Customer Rating:  4.8 out of 5 stars   (68 Customer Reviews)


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Good product and customer service is excellent to deal with!!



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Good job



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Great thanks



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Fast good service



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I think I got in over my head but had a smart neighbor able to mount this pin and attach to my trailer.



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Arrived quickly. Product is exactly what I needed



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Parts were good quality, fit as they should. Delivery arrived on time and undamaged



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These are great weld on kingpins



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works great



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Exactly what we needed, makes repairs a breeze.



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Fits good. Works well for my applicati on



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Order was processed and shipped within an hour of my placing it! Arrived in excellent shape very quickly.



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awesome,thats why I continue to order from yall,very fast shipping,i love it!



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Great product, reason for a three is they shipped this 8 pound weight with plastic items and Butyl tape that got all broken apart and squished in shipping.



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I welded a hook on the back of this unit and when needed, attach it to our overhead hoist. This make installing the fifth Wheel hitch fully assembled into the truck bed - VERY EASY!



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Again thanks for the prompt speedy shipping. I am all the way across the country from shopping location and I get products faster than I do from neighboring states. It’s hard to believe. Keep up the awesome work, anymore I don’t even look at competitor companies just because of the positive transactions and quick shipping times.



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great product and fast shippin



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Worked great.



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George, yes thanks this hitchpin got me back on the road just in time for the fall last year!! Thanks!!



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I installed the King Pin into a Goose Neck and customer is very satisfied. I liked the quality of the material the pin is made from. Welding using 1/8" E7018 was a snap!



by:

This king pin appears to be a great product. Usa made and just as described. Shipping was fast and accurate. Definitely satisfied with the product and service i have received from etrailer.com! They have totally earned a repeat customer.


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See what our Experts say about this Buyers Products 5th Wheel Pin Box

  • Does Curt E16 5th Wheel Hitch Fit Curt Universal Base Rails
    They are! The Curt hitch and base rail kit you asked about are 100 percent compatible: - Curt E16 5th Wheel Trailer Hitch # C16115 - Curt Universal Fifth Wheel Base Rails with Installation Kit # C16200 This will give you industry-standard base rails, which the E16 hitch will mount right into so you can tow your 5th wheel trailer.
    view full answer...
  • Replacement Kingpin for Part Number A52478-1
    I may have a solution for you, but I don't see a lot of information about the part numbers that you provided; when I researched this the only thing I found says that the A52478-1 is a standard 2" kingpin that was used on military trailers. If this is the case then the Buyers Products # 337KP20031 will work for you. We do not have a 3-1/2" kingpin available, which would be the next largest size.
    view full answer...
  • Why Do King Pin Replacements Have Different Bolster Thicknesses
    King pins can be found on a variety of different trailer types; 5th wheel, gooseneck, RVs, campers, lawncare, excavating, and car haulers just to name a few. So if you're just replacing the king pin you will want to use one that has a matching bolster plate thickness: 1/4" - # 337KP20025 5/16" - # 337KP20031 3/8" - # 337KP20038 1/2" - # 337KP20050 Attached is a review video for you to check out.
    view full answer...
  • Solution for Extending King Pin to Gain Clearance Between 5th Wheel Trailer and Truck
    The Buyers Products 2" Forged SAE Trailer King Pin # 337KP20031 is a universal option that's designed to simply replace an existing king pin. It is not an extender but simply a standard king pin that would be welded to your trailer after the existing unit is removed/cut off. If you are needing to extend the king pin to raise the trailer's height where it connects to your truck then a better option will be to raise the entire pin box assembly. There should be adjustment holes on the pin...
    view full answer...

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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Cole B
Installed by:
Cole B
Employee Kristina F
Written by:
Kristina F

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