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

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

Item # 337KP20031
(45 Reviews)
Retail:$125.27
Our Price: $76.41
You Save: 39%
Fifth Wheel King Pin
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Shipping Weight: 13 lbs
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Buyers Products Fifth Wheel King Pin - 337KP20031
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Buyers Products Fifth Wheel King Pin - 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





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

Buyers Products Fifth Wheel King Pin

45 Reviews

Code: 337KP20031

In Stock

Retail:$125.27
Our Price: $76.41
  • Fifth Wheel King Pin
  • King Pin Only
  • Buyers Products


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This Rota-Flex pin box has a pivoting head with a built-in rubber compound that works to reduce chucking and absorb road shock, resulting in a smoother ride and less wear and tear on your trailer. Replaces Lippert 1621 or 1621HD pin boxes.

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Flex Air drastically reduces chucking, absorbs road shock, and minimizes bounce. The internal air bag and built-in strut work with the rubberized pivoting head to achieve a dramatically smoother ride. Replaces Lippert 1621 pin boxes.

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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   (45 Customer Reviews)

by:

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




by:

Good job




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by:

Fast good service




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by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


Awesome service, parts came quick, and the right parts, I will be ordering again thanks etrailer.com




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


When we received this it was exactly what we ordered and worked out great. We will be ordering more to come from etrailer.com
Thank you.




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


All products where as described. Very pleased with price, delivery time and quality.




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


Great replacement for Holland pins




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


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.


Comments
I will have our customer service team reach out to you.
-- Etrailer Expert Jenny N - 02/19/2022


by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


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!




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


etrailer is awesome!! The rep I dealt with knew EXAACTLY what I wanted. Very helpful, quick service and very polite. Big thumbs up!!




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


These are great weld on kingpins

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by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


Works as desired for a trailer repair we did in house.




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


Great Product




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


Just what we were looking for, and etrailer had it. Great customer service!




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


USA made, excellent




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


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

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by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


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.




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


great product and fast shippin

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by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


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:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


Absolutely the best service. We seem to be living in a world where vendors don't care and customer service has gone to the wayside. I thank God that there are still some vendors that take customer service above and beyond. Great job etrailer.




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


Very good product well made and easy to install. Don’t know how others get along without one so convenient and easy to hook up to trailer now




by:

Review from a similar Forged SAE King Pin in Fifth Wheel King Pin


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



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See what our Experts say about this Buyers Products Fifth Wheel King Pin

Do you have a question about this Fifth Wheel King Pin?
  • 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...
  • 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...
  • 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...

Do you have a question about this Fifth Wheel King Pin?




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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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