Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate - Weld On

Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate - Weld On

Item # 337KP20050

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Fifth Wheel King Pin

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Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate - Weld On 337KP20050
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  • Buyers Products
  • Universal King Pin
Call 800-298-8924 to order Buyers Products fifth wheel king pin part number 337KP20050 or order online at etrailer.com. Free expert support on all Buyers Products products. Guaranteed Lowest Price and Fastest Shipping for Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate - Weld On. Fifth Wheel King Pin reviews from real customers.


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  • Reviews (3)
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  • Videos (1)
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Buyers Products Fifth Wheel King Pin - 337KP20050


Buyers Products 2" Forged SAE 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 1/2" 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: 1/2"
  • Bolster plate hole thickness: 3"
  • Forged steel construction
  • Plain finish
  • Made in the USA


KP20050 Buyers Products 2 Inch Forged SAE Trailer King Pins With 1/2 Inch Bolster Plate - Weld On







Video of Buyers Products 2" Forged SAE Trailer King Pin with 1/2" 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 - 337KP20050 Review

Speaker 1: Today we're taking a look at a two-inch Forged SAE Trailer King Pin. The Trailer King Pin provides strength and reliability in coupling your fifth wheel. It's forged from AISI8630 steel and heated treated to maintain a hardness 302-363BHN and 150,000 PSI in ultimate strength. Now, the King Pin has a half-inch thick bolster plate. That's the measurement of this portion right here. From this plate to the edge of the lift, that's a half inch.

It's made from forged steel and has a plain finish, and it's a weld on installation. The overall diameter of the unit is eight inches from very bottom to very top. I'll leave that flat edge up there, and I'll measure up to that. That's going to give us a measurement of about four and a half inches. Then, if we take a measurement from bottom, to the bottom of this plate here, that's going to give us a measurement of about three and 13/16 to three and 7/8 inches.

Right in that area.Now, this portion here, this has a diameter edge to edge of two and 13/16 inches. This right here has a diameter of two inches, and then the base has a diameters of three inches. Again, nice durable forged steel construction, and the product's made in the U.S.A. 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 1/2" Bolster Plate - Weld On - 337KP20050

Average Customer Rating:  5.0 out of 5 stars   (3 Customer Reviews)


- 337KP20050
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. 585774



- 337KP20050
by:

great product and fast shippin 699816



- 337KP20050
by:

I have been using these for years from a different supplier. 683222


3
3

Ask the Experts about this Buyers Products Fifth Wheel King Pin

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


  • Recommended Gooseneck Hitch Ball to 5th Wheel Trailer Adapter
  • The Fifth Wheel Trailer King Pin # 337KP20050 is a weld on king pin to make your trailer compatible with 5th wheel hitches. If you want the gooseneck trailer to 5th wheel king pin adapter, you can use the Ram Gooseneck to 5th Wheel Trailer Coupler Adapter Inner Tube - Square # KPG5-Q30IP or round # KPG5-R30IP. If you have a gooseneck hitch installed in your truck and you have a 5th wheel trailer, then you will want the Demco Recon Gooseneck-to-5th Wheel Trailer Hitch Adapter # DM8550045...
    view full answer...

  • Troubleshooting Reese Low-Profile 5th Wheel Trailer Hitch # RP30054 That Doesnt Fit Camper Kingpin
  • The Reese Low-Profile 5th Wheel Trailer Hitch - Dual Jaw - 30,000 lbs # RP30054 is confirmed to fit the standard 2 inch diameter king pins. Use a digital caliper like # PTW80157 to measure the inner diameter of the closed jaws and the external diameter of the king pin. I've attached a photo of the detailed dimensions of a standard king pin to help. If the hitch is the issue, then you will need to return it for a properly functioning model as there is no adjustment of the hitch jaws. If...
    view full answer...

  • Weld Installation Universal King Pin Replacement
  • The Fifth Wheel Trailer Universal King Pin # 337KP20050 has welding procedures in accordance with the American Weld Society. They don't have specific specifications, so I recommend utilizing a professional welder for installation to ensure the weld will be the correct strength for your trailer.
    view full answer...

  • Can A Fifth Wheel Be Used With An Inverted Fifth Wheel On A Trailer Using A Fabricated Dual King Pin
  • This is the first time I have heard of the issue you are describing. It sounds like there is an inverted fifth wheel hitch on the trailer you are trying to deal with. The best solution I could recommend would be to remove the inverted fifth wheel on the trailer and install a king pin like part # 337KP20050. I am not certain about the legality of the dual fifth wheel hitches being used with a fabricated dual king pin. You will need to check with the Department of Transportation in...
    view full answer...

  • Can I Tow a 5th Wheel Travel Trailer with a Semi Truck or 18-Wheeler
  • The king pin dimensions can be the same between fifth wheel trailers and large commercial trailers. Both types of trailers often use a standard 2 inch king pin although semis sometimes have a 3-1/2 inch. As long as your truck fits a 2 inch king pin it can work. Semi trucks were not technically designed to tow camping style fifth wheel trailers, so there are several factors that you will want to take into consideration before attempting to tow. First, you will want to make sure the...
    view full answer...

  • Recommended King Pin for Custom Pin Box
  • We do not custom engineer pin boxes as there is a lot of testing required to ensure a fit as well as determine compatibility. If you want to have a pin box custom made by a local welder to meet your specifications, then you can use the Buyers Products # 337KP20050 to give you the standard king pin that will work with 5th wheel trailer hitches.
    view full answer...

  • Fifth Wheel Adapter Options Other Than King Pin to Gooseneck Ball
  • We don't have a 2 inch receiver application, but we do have the B&W Turnoverball King Pin Adapter for Trailers with Inverted 5th-Wheel Hitches # BWGNXA4000 which is a 2-1/2 inch outer measurement on the solid square. We also have the Fifth Wheel Trailer King Pin # 337KP20050 with no connection on the backside if you need to make a custom adapter If you are looking for a gooseneck to king pin connection, we have the Gooseneck to 5th wheel adapter inner tube # KPG5-Q25-IP which has a...
    view full answer...

  • When to Replace a Trailer King Pin Based on DOT Regulations
  • The Fifth Wheel Trailer King Pin # 337KP20050 is 2 inches diameter where the jaws of the 5th wheel hitch will connect. Typically the max wear on a king pin is .080 of an inch with a minimum diameter of 1.920 before manufacturers recommend replacement. DOT says the max wear is .125 of an inch with a minimum diameter of 1.875. I did not find any specs for non-commercial trailer king pin requirements from the Federal Government. You can find all the federal information for commercial...
    view full answer...

  • Can a 5th Wheel Hitch Rated for Recreational Use be Used for a Commercial Trailer
  • It is possible that you can tow a commercial trailer with a 5th wheel hitch rated for recreational use but it is not really a good idea for an extended period of time. The first issue as to why it might not be a good idea is because of the kingpin dimensions. The standard kingpin used on recreational trailers is 2" diameter. This is also the size used on most commercial trailers as well but they could utilize a 3-1/2" diameter kingpin so you will need to check this beforehand. If it does...
    view full answer...

  • Maximum Amount of Wear 5th Wheel Trailer King Pin Before Replacement
  • Typically the max wear on a king pin is .080 of an inch with a minimum diameter of 1.920. DOT says the max wear is .125 of an inch with a minimum diameter of 1.875. When new the king pin will have 2 inches of diameter. See the image I made for you showing the dimensions of a weld on king pin.
    view full answer...


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Info for this part was:

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

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