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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
Retail:$125.60
Our Price: $73.27
You Save: 42%
Fifth Wheel King Pin
This item qualifies for Free Shipping
Shipping Weight: 13 lbs
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Buyers Products King Pin Only - 337KP20050
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Buyers Products Fifth Wheel King Pin - 337KP20050

  • Buyers Products
  • King Pin Only


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 Satisfaction Score:


Customer Reviews

Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate - Weld On - 337KP20050

Average Customer Rating:  4.8 out of 5 stars   (43 Customer Reviews)


by:

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




by:

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:

These are great weld on kingpins




by:

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




by:

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




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.




by:

great product and fast shippin




by:

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:

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:

Worked great




by:

Thanks for taking care of me Etrailer.




by:

The service was outstanding and the rapid shipping was very appropriated.




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great product




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




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got my order fast




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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


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


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


Great replacement for Holland pins




by:

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


Great Product



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

  • 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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  • 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 the...
    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...
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  • 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...
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  • 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...
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  • 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...
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  • Will the Buyers Products 2" Forged SAE Trailer King Pin Fit a Semi Tractor
    The Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate part # 337KP20050 should work just fine on a semi-tractor since both they and RV's use a standard 2" diameter kin pin.
    view full answer...
  • Availability Of A King Pin For 5th Wheel Trailer
    We do offer just the king pin like the Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate # 337KP20050 which gives you the standard 2" king pin for use with a 5th wheel hitch. It is a good idea to have a qualified welder install the king pin, as the welds need to be sound to support the weight of the trailer. I included a video of the Buyers # 337KP20050 for you to take a look at.
    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...
  • Bolt Size Needed For Buyers Products 2 Inch Forged SAE Trailer King Pin 337BKPT809B
    The bolts do not come with the Buyers Products 2" Forged SAE Trailer King Pin with 1/2" Bolster Plate - Bolt On # 337BKPT809B. So I did check with the manufacturer, Buyers Products, and they told me the bolts needed to be 1 inch long x 1/2 inch. As far as procedure, there isn't one I can offer as it will differ depending on the application and is a project for professional fabricators. As for which is better, this bolt-on has the exact same specs as the weld-on # 337KP20050 king pin...
    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...
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  • Does 2009 Dodge Ram 2500 Short Bed Need Slider Hitch Towing 2014 Keystone Sprinter 314 FWRLS
    In general a sliding hitch is needed when towing a fifth wheel trailer with a truck that has a bed shorter than 8 feet. There are scenarios where a slider hitch isn't needed though like if the trailer happens to have a tapered nose. I looked up your 2014 Keystone Sprinter 314 FWRLS and the nose of it is tapered the pin box is extended and since your short bed truck is a bit longer at 6.5 foot (a lot are shorter than that) I'd think you'd most likely not need a slider. If it were me I...
    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 4...
    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 truck...
    view full answer...
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  • 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...

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 Jameson C
Expert Research:
Jameson C
Employee Cole B
Installed by:
Cole B
Employee Kristina F
Written by:
Kristina F

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