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Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches
Demco

Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches

Part Number: DM8551000
In Stock
$589.79
Retail:$807.67
You Save: $217.88
5th Wheel Hitch Rails

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Custom, underbed rail kit allows for uninhibited use of your truck bed once your hitch is removed. Works with Underbed Mount Series (UMS) fifth-wheel and gooseneck hitches. No-drill frame brackets offer a simple installation. 1-800-940-8924 to order Demco 5th wheel hitch rails part number DM8551000 or order online at etrailer.com. Free expert support on all Demco products. Great prices and Fastest Shipping for Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches. 5th Wheel Hitch Rails reviews from real customers.
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  • Reviews (26)
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2008 Ford F-350 Super Duty - Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches

  • Below the Bed
  • Custom
  • Demco

Custom, underbed rail kit allows for uninhibited use of your truck bed once your hitch is removed. Works with Underbed Mount Series (UMS) fifth-wheel and gooseneck hitches. No-drill frame brackets offer a simple installation.


Features:

  • Installation kit is designed for use with Demco UMS 5th-wheel and gooseneck trailer hitches
  • Underbed rails allow for complete access to truck bed when hitch is removed
    • No exposed rails
    • 4 Mounting holes sit flush with truck bed
  • Vehicle-specific design reduces installation time and requires less drilling than universal systems
    • No-drill brackets bolt onto the outside of your truck's frame rails
    • Crossmembers sit along top of frame rails, beneath bed
  • Sturdy, black powder coated steel resists corrosion
  • Rails and installation hardware included
  • Made in the USA


Specs:

  • Application: Demco Underbed Mount Series (UMS) 5th-wheel and gooseneck trailer hitches
  • 5-Year limited warranty


8551000 Demco Hijacker UMS Under Bed Rail Frame Bracket Kit

Installation Details DM8551000 Installation instructions

Customer Satisfaction Score:


Customer Reviews

Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches - DM8551000

Average Customer Rating:  4.7 out of 5 stars   (26 Customer Reviews)

Custom, underbed rail kit allows for uninhibited use of your truck bed once your hitch is removed. Works with Underbed Mount Series (UMS) fifth-wheel and gooseneck hitches. No-drill frame brackets offer a simple installation.

by:
Ford Transit Connect

Great product , easy to understand instructions, and a perfect fit. Customer service was also top notch had a problem with the first order missing rail fell out of the box in transit , no fault on etrailer, they sent me a new order before the old one was picked up! Fantastic customer service, I will definitely order from etrailer again!

Wil K.

2/17/2020

Everything has been working great, no problems at all!



by:
2014 Ford F-250 and F-350 Super Duty

The under bed rail kit was easy to install. It provides easy removal and installation of the Demco Autoslide 5th wheel hitch. I could not be more pleased with the Demco products. I recommend getting the Demco 5th Wheel Lifting Bracket
Item # DM6100. It makes removal and installation of the hitch a breeze.



by:
Ford F-350 Super Duty

Instructions left alittle to interpretation when it came to hitch height in the bed of the truck. For a f350 super duty it is the medium set up. Save you some time and effort. Other then that it looks great and will be testing it out this weekend.



by:
2006 Ford F-250 Super Duty

Only issue I ran into with my truck is that using the supplied measurements the back holes hit 1/4 on the bed rail. Still large enough to install the cross bars and hitch but something to be aware of. Truck was a 2006 F250 lariat 2wd with 6.5 box



by:

Not to difficult to install. It will require 2 people to get the bolts torqued down. Handles a 14000 lb fifth wheel with ease



by:

The under bed mount for the demco auto slide was easy to install with easy instructions and works great

Tony C.

7/9/2018

The under bed rails and Demco hitch are great. I have put 20 thousnd miles on them with 13,654 pounds of fifth wheel trailer



by:

Perfect fit. Planned ahead and had put on an Airlift 5000 with the auto level system. Adding this under bed mount for my hijacker auto slide on my 2015 F250 was simple and bolted right up with my airbags.

etrailer customer service was great in helping me make sure all the parts I ordered won’t play nice together.



by:
2006 Ford F-250 and F-350 Super Duty

Hitch appears to be well-constructed and sturdy. I have not yet installed it. Some assembly is required, and the instructions aren't crystal clear. Better illustrations would be helpful. The videos online are the best source of installation information. Shipping materials lack protection. The powder coating was damaged in a few locations, as well as the instructions. I expect the hitch will operate exactly as designed a long as I protect the exposed parts from the inevitable elements. Rubber grommets would be a nice addition to the holes drilled in the truck bed.



by:

It’s a pleasure doing business with your company and getting products in a timely manner.

Stanley

8/2/2023

Don’t have problem with parts , it is the service . The first time I ordered everything went great and on time . The bext time I ordered all my parts wasn’t there , I was told I would receive missing parts the day day before my travel . Then I get confirmation email that I was gonna receive my parts two days after my leave date to be told there isn’t anything they could do . Why should I lose out on my week stay in key west at a night because they didn’t send me my parts I ordered way before my leave date .



by:

worked perfect.no drilling! well worth buying this instead of the universal kit. and no rails in the bed!

Buddy R.

3/24/2019

great!



by:

Timely delivery. Product was very well packaged. All parts where clearly marked and instructions are well writen.



by:
2008 Ford F-350 Super Duty

Installed the kit on my 08 ford f350 srw crewcab diesel. Fit fine. Well made. I just think the passengers side center bolt washer/extension piece was welded on the wrong side. I did a backyard fix , buy cutting a small filler piece out of steel so the frame plate wouldn't suck up to the frame and bend. Otherwise, good strong steel



by:

Great design. Installation wasn't bad at all (plan on buying a carbide drill bit). Hole plugs just cheap plastic.



by:

Arrived on time and in good condition. Instructions were good a bit hard to install on drivers side. But that’s the truck not the part. Part had no issues with fit



by:
2013 Ford F-350 Super Duty

Easy to install.

Darin

3/11/2023

This hitch has been working flawlessly for the past year. I would definitely recommend this hitch to anyone that is looking for a great sliding fifth wheel hitch.



by:
2012 Ford F-250 and F-350 Super Duty

Just as described. Install was very easy.it had one base rail missing and called and talked to Sheila and she sent another one out. Had to set up our camper for a new job we are starting and needed the part in two days. She overnighted it and it was here on time.
Rod



by:
2012 Ford F-250 and F-350 Super Duty

Excellent product, it is fairly easy to install.



by:
2008 Ford F-250 and F-350 Super Duty

Great product, drill 4 holes and you are done, simple.



by:

Was easy to install with very few tools.



by:

Same as one



by:
1999 Ford F-250 and F-350 Super Duty

nice product fit was good. prompt shipping.



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Show More Reviews

See what our Experts say about this Demco 5th Wheel Hitch Rails

  • Estimated Installation Time For Demco Fifth Wheel Hitch And Installation Rail Kit
    Hey Clint, you are going to be installing the rail kit on the truck as well, correct? The Demco Recon 5th Wheel Trailer Hitch # DM47YV by itself should take only about 30 mins to assemble and install. The Installation Rail Kit # DM8551000 will also need to be installed on the truck. For the Installation Rail Kit, we estimate about 4.5 hours for installation. So, for the hitch and rail kit you would be looking at around 5 hours. You will find our install video linked below.
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  • Can Demco Autoslide 5th Wheel Hitch Fit 2011 F-250 With B&W Turnoverball Gooseneck Hitch
    I have two options for you, but you won't be able to use your Demco Autoslide with the B&W Underbed Installation Kit. You can't mount additional rails with the B&W hitch installed, and you can't use an adapter since it is unable to withstand the torque from the autoslide. The first option is to sell the Demco and get a B&W Companion # BWRVK3400-5W. The other option is to remove the B&W underbed hitch and install new rails to work with your Demco. You can choose above or below bed rails...
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  • Automatic Sliding Fifth Wheel Hitch Recommendation for 2016 Ford F-250 6-3/4 foot Bed
    For a 6-3/4 foot bed you would want to use a slider hitch still. Basically anything shorter than 8 feet is going to require a slider hitch unless the nose of the trailer was specially designed for turning clearance with a short bed truck. I have a great slider hitch solution that I can provide though. The Demco Hijacker AutoSlide part # DM8550022 will automatically slide back and give you turning clearance while making sharp turns. This way you will avoid the hassle of having to get out...
    view full answer...
  • Below Bed Base Rails for 2002 Ford F-250 and Demco Hijacker Autoslide 5th Wheel Trailer Hitch
    You can absolutely use the 18,000 lb Demco Hijacker Autoslide with the underbed rails on your 2002 Ford F-250 crew cab. What you need are the following: - Underbed Rail and Installation Kit for Demco Hijacker # DM8551000 - Demco Hijacker Autoslide 5th Wheel Trailer Hitch with Slider - 18,000 lbs # DM8550022 As you mentioned, this is also compatible with the 21,000 lb version of the Hijacker # DM8550037. Additionally, if your '02 F-250 has the factory 7-way but you need a 5th wheel wiring...
    view full answer...
    Image 1 for
  • Is a Sliding 5th Wheel Hitch Needed to Tow with a 2007 Ford F-350 Diesel with Short Bed
    Although some people can make it work, for any pickup with a bed less than 8' we always recommend going with a sliding 5th wheel hitch. This allows you to safely make sharp turns without your 2004 Forest River Cedar Creek making contact with the cab of your 2007 Ford F-350. You actually don't need a capture plate unless your pin box has a rotating turret, like a Sidewinder, or you have an automatic sliding 5th wheel hitch. If you have a normal pin box then no special capture plate is required. If...
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    Image 1 for
  • Recommended Sliding Hitch For A 2005 Ford F-250 Super Duty With B&W Gooseneck Hitch
    The Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed - 18,000lbs # DM8550022 does not attach via gooseneck hitch and instead attaches using base rails like # DM8551000 or # DM8552002-71. For you to be able to use this hitch you would need to remove the B&W Gooseneck Hitch # BWGNRK1108-5W you currently have in the bed of your 2005 Ford F-250 Super Duty and install a base rail system instead. If you want a compatible sliding hitch for your gooseneck hitch...
    view full answer...
  • Underbed Demco Hijacker Hitch Recommendation for 2016 Ford F250 Short Bed
    We have an under bed Demco Hijacker fifth wheel hitch setup that is confirmed as a fit for your 2016 Ford F-250 6-3/4 foot bed. For that you would want to start with the underbed rail kit, part # DM8551000. Then for the automatic sliding hitch you'd want the part # DM8550022 which is the 18k Demco Hijacker you said you were interested in. There isn't a way to use the Curt hitch you have though.
    view full answer...
  • How Much Does the 18K Demco Hijacker Autosliding 5th Wheel Hitch # DM8550022 Weigh
    If your 2013 Ford F-250/F-350 has the 6-3/4 bed you can use the Underbed Rail and Installation Kit # DM8551000 so that you can use the 18K Demco Hijacker Autosliding 5th Wheel Hitch # DM8550022 that you referenced. The Demco Hijacker # DM8550022 weighs about 280 lbs. The head can be removed (which weighs about 62 lbs) to help make lifting the hitch a little easier though. If you have a standard Lippert 1621 pin box then no plate is needed for hooking up your trailer. The capture brackets...
    view full answer...
  • 5TH Wheel Rail Kits and Hitches For a 2016 Ford F-350 Without Factory Prep/Puck System
    You will have several options for mounting a 5th wheel hitch in your 2016 Ford F-350. First is the Curt Custom 5th Wheel Installation Kit for Ford # C16424-204. This system gives you rails that will mount inside your bed and accept either a Sliding Hitch # C16541 for a short bed or Fixed Hitch # C16130 for a long bed. This system does mean that you will have the rails that are always in your bed which can be a hassle if you do slide things in and out of you bed a lot. Next is the B&W...
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  • Underbed Fifth Wheel Slider Recommendation for 2016 Ford F-250 That Slides Automatically
    If you are looking for an underbed fifth wheel rail kit that allows the install of a Demco Hijacker Autoslide we have just what you need for your 2016 Ford F-250 without the factory rail kit. For that you would need the part # DM8551000 for the rail kit. And then for the 18k Hijacker to fit the rails (without needing an adapter), you would want the part # DM8550022. If you needed the 21k Hijacker you instead would want the part # DM8550037.
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  • 5TH Wheel Hitch Adapter for 2009 Ford f-350 OEM to Industry Standard Rails
    I believe the factory Ford 5th Wheel Prep didn't enter the market until 2011. So I wonder if someone installed the same OEM style system or did a different underbed mounting system. If you are not 100% sure check the measurements. For the Ford OEM Mount, Demco 5th Wheel Rail Adapter for Ford OEM 5th Wheel Towing # DM6175. This converts the OEM mount to the Industry Standard above bed rails. These holes will be 13" center front to back and 30" on center side to side. There will also be...
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  • Parts Needed To Mount A Demco Recon Slider Hitch In The Bed Of A 2013 Ford F-350
    Hey Larry, Your installer is correct about factory puck systems needing to be installed at the factory and would not be an option aftermarket. Luckily, Demco does have an underbed mounting system for your 2013 Ford F-350 with part # DM8551000. From there you can just swap out the side plates with part # DM44YV to switch from Ford's puck spacing to Demco's.
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  • Do Demco Hijacker Locking Plates Have to Be Set Every Time You Tow Trailer
    The locking plate of the Demco Hijacker part # DM8550037 is something that installs onto the king pin of the trailer you will be towing to prevent the king pin from turning in the hitch head. The plate allows the head of the hitch to turn with the trailer which activates the slider portion of the hitch. It would only require the initial installation. I attached a page that has all of the locking plates we offer.
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  • 5th Wheel Trailer Hitch and Installation Kit for a 2015 Ford F-250 Short Bed
    The design of your Keystone 5th wheel trailer is indeed designed for use with short bed trucks without having to use a slider hitch. However, a slider can still be used and would be a good idea if you ever tow a trailer that does not have the short bed friendly design. For an under bed mount for your 2015 Ford F-250 I recommend Demco kit # DM8551000 and for a hitch I recommend # DM8550022. The great thing about this hitch is that it will slide automatically without you having to do anything....
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  • Recommendation for Underbed 5th Wheel Hitch on 2015 Ford F-250 with 6-3/4 Foot Bed
    I do have a couple options for you, however the 18 K Demco Hijacker Autoslide 5th Wheel Trailer Hitch # DM8550034 referenced in your question is not compatible with below-bed rail kits. For this 5th-Wheel Hitch, you will use the above bed rail kit # DM8552000-71. If you would like to use a below-bed rail kit, I recommend the Demco Hijacker Autoslide - Underbed # DM8550022 along with the rail kit # DM8551000. This hitch is also rated at 18,000 pounds and has a premium single-piece jaw...
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  • Which 5th Wheel Mounting Kit for Demco Hijacker Autoslide on 2008 Ford F-350 Short Bed
    To install a Demco Hijacker Autoslide # DM8550037 on your 2008 Ford F-350 short bed you'll need the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches # DM8552001-71. This kit provides you the above bed installation rails needed to mount your Hijacker. If you don't already have a 7 way plug in your truck bed, adding one provides you a much more convenient plug in location for your 5th wheel trailer's wiring; you can add a 7 way plug using...
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  • Auto Slider Fifth Wheel Hitch for 2013 For F-250 Short Bed
    There are a lot of great options for fifth wheel hitches for your 2013 Ford F-250, but the Demco Hijacker # DM8550024 is for use with Ford F-250 models that have the OEM Prep Package. Since you do not have the OEM Prep Package, I recommend the Demco Hijacker Autoslide 5th Wheel Trailer Hitch # DM8550022 and the Underbed Rail and Installation Kit for Demco Hijacker # DM8551000. This is the same autoslider system with a 18,000 lbs gross trailer weight capacity, it just has a different base...
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  • Installation of Locking Plate for AirRide Pin Box with Demco 5th Wheel AutoSlide Hitch
    The instructions state that with the use of the Demco Adapter Plate # DM6095 the locking plates on hitch head are not needed when using this kit. They can be extended all the way out or removed. Per Demco the # DM6095 is only compatible with the Trailair Tri-Glide Pin Boxes. I really like the Demco Hijacker's AutoSlide technology because you never have to get in or out of your bed to adjust the hitch from towing to turning, it just automatically takes care of it for you. The Demco AutoSlide...
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  • Under Bed Fifth Wheel Rail Kit Recommendation for 2001 Ford F-350 Short Bed
    I attached a link to this page that has all of the under-bed fifth wheel hitch solutions we have for your 2001 Ford F-350 short bed. I really like the automatic sliding hitch from Demco part # DM8550022 with the rail kit part # DM8551000 which is the best option but for a standard slider the Companion part # BWRVK3400 with the rail kit part # BWGNRK1108 would also be an awesome option.
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  • Below-Bed Base Rails for 5th Wheel Trailer Hitch on 2014 Ford F-250, F-350 Super Duty
    The only rail Husky offers for their sliding hitches for your 2014 Ford F-250 or F-350 Super Duty is the Husky Custom Base Rails and Installation Kit # HT31408-686. These rails are above-bed rails. Reese, Demco, and B&W offer below-bed rails for their sliding 5th wheel trailer hitches for your F-250 or F-350. I recommend the Demco Hijacker Autoslide 5th Wheel Trailer Hitch with Slider # DM8550022 and the Underbed Rail and Installation kit for Demco Hijacker Underbed Mount Series # DM8551000....
    view full answer...
  • 5th Wheel Trailer Hitch and Install Kit for a 2008 Ford F-350 Short Bed and 2010 Keystone Cougar
    Since your 2008 Ford F-350 is a short bed I recommend going with a slider hitch so you will have more clearance between trailer and truck cab when making tight turns. The slider hitches that offer the most travel are the Demco HiJacker auto-sliders, # DM8550022 for below the bed rail kit # DM8551000, or # DM8550034 for above the bed rail kit # DM8552002-71. These hitches also have the benefit of sliding automatically. This means you won't have to get in an out of the truck repeatedly...
    view full answer...
  • Slider Fifth Wheel Hitch Recommendation for 2015 Ford F-250 that Uses Underbed Rails
    For your 2015 Ford F-250 without the factory rail kit to use a Companion Slider hitch part # BWRVK3400-5W you will have to use the Turnoverball Gooseneck Hitch part # BWGNRK1111-5W. The only other solution I would have you consider is the Demco Hijacker Auto Slide part # DM8550022. You can install this hitch with an under bed rail kit as well, part # DM8551000 which is confirmed as a fit for your truck. The great thing about this hitch is that it slides automatically as you make tight...
    view full answer...
  • Can I Hitch Up My 5th Wheel Trailer at a 90 Degree Angle?
    I would not recommend hooking up at a 90 degree angle for a couple of reasons. The trailer is not designed to take the force of the truck contacting the pin box at that angle. It would be very dangerous and unstable and could topple the trailer over if something were to hit it too hard. The front of the pin box has a curved lip to let the pin box ride up the hitch head. The side of the pin does not have that lip so everything would have to be extremely precise to make sure the flat...
    view full answer...
  • 5th Wheel Trailer Hitch and Under-Bed Install Kit for a 2016 Ford F-250 Short Bed
    I recommend the Demco HiJacker auto-sliding 5th wheel trailer hitch # DM8550022 for your 2016 Ford F-250 short bed. This hitch is rated for 18,000 pound gross trailer weight so it can easily handle your 16,000 pound trailer. This hitch also slides 14 inches automatically for clearance when turning; all without having to get in an out of the truck! I have included a link to a video review for you. For an under-bed installation kit I recommend # DM8551000 which is a custom kit for your...
    view full answer...


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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Adam R
Expert Research:
Adam R
Employee Jeffrey L
Expert Research:
Jeffrey L
Employee Jeff D
Installed by:
Jeff D
Employee Joshua S
Video by:
Joshua S
Employee Zach D
Video by:
Zach D
Employee Jacob T
Video Edited:
Jacob T
Employee Dustin K
Video Edited:
Dustin K
Employee Laura H
Updated by:
Laura H
Employee Wilson B
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Employee Hannah L
Updated by:
Hannah L
Employee Kristina F
Updated by:
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