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

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

Item # DM8551000
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Fifth Wheel Installation Kit

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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. 1-636-306-4830 to order Demco fifth wheel installation kit part number DM8551000 or order online at etrailer.com. Free expert support on all Demco products. Guaranteed Lowest Price and Fastest Shipping for Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches. Fifth Wheel Installation Kit reviews from real customers.
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2011 Ford F-250 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 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   (25 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!


Comments
Everything has been working great, no problems at all!
Wil k - 02/17/2020


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:

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:
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:

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




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:

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:
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:
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:

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


Comments
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
Tony C - 07/09/2018


by:
2013 Ford F-350 Super Duty

Easy to install.




by:

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


Comments
great!
Buddy R - 03/24/2019


by:

Same as one




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:

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




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:




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

nice product fit was good. prompt shipping.




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See what our Experts say about this Demco Fifth Wheel Installation Kit



  • Are the Instructions in the Demco Installation Kit Correct for a 2015 Ford F-350 6-3/4ft Bed
    My contact a Demco confirmed that the Demco Installation Kit # DM8551000 is the correct kit for your 2015 Ford F-350 Super Duty. They explained that these instructions have not be updated to reflect the 2015 year, but the kit will fit Ford models up to at least 2016.
    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...
  • Automatic Sliding Fifth Wheel Hitch Recommendation for 2015 Ford F-250 Short Bed
    For your 2015 Ford F-250 without the factory rail kit and a short bed we have just what you would need. Since you do have a short bed truck you are correct and you would need a slider hitch. My favorite to recommend is the Demco Hijacker part # DM8550022 which automatically slides as you make tight turns. This eliminates the hassle of having to get out and activate the slider. For a rail kit you then would want the under bed kit part # DM8551000 which will fit the hitch and then when not...
    view full answer...
  • Demco Hijacker AutoSlide 5th Wheel Hitch Compatibility With Trailair Rota-Flex Pin Box
    For your 2015 Ford F-350 6-3/4 foot bed without Factory Rail Kit, the Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed - 18,000 lbs # DM8550022 with the Underbed Rail and Installation Kit # DM8551000 is a confirmed fit. There is no need for a different capture plate for using the Trailair Rota-flex Pin Box. It will be compatible with the hitch. The only pin box that is not compatible is the Revolution pin box or the aftermarket Reese Sidewinder because...
    view full answer...
  • 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.
    view full answer...
  • 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...
  • 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...
    view full answer...
  • Under Bed Demco Rail Kit for Use with Hijacker Autoslide Fifth Wheel Hitch
    Yes, Demco does have an underbed rail setup that is a confirmed fit for your 2008 Ford F-250 short bed with the part # DM8551000 which would allow you to use the Hijacker Autoslide part # DM8550037 that you mentioned.
    view full answer...
  • Is Drilling Of Frame Or Exhaust Removal Required When Installing Demco Hijacker On 2016 Ford F-350
    When installing the Demco Underbed Rail and Installation Kit, part # DM8551000 on your 2016 F-350, no drilling is done to the frame and the exhaust does not have to be moved or removed to complete the installation. The Demco Hijacker, part # DM8550032 will work great with your truck. This fifth wheel hitch has a wraparound single-jaw that gives you 360-degree jaw to king pin contact. This hitch hasa 21,000-lb gross towing weight. If you need a 7-way connector for your fifth wheel I recommend...
    view full answer...
  • Recommended Auto-Slide 5th Wheel Hitch for 2016 Silverado 1500 Double Cab
    The 2017 Jayco Eagle 29.5FBDS has a gross trailer weight rating of just under 10K. Page 333 of the online manual for your 2016 Silverado 1500 indicates a towing capacity for the double cab with regular bed that ranges across the engines types from a low of 11K up to 17.7K so the truck seems good to go. I still suggest checking your manual. I recommend a custom-fit 5th wheel base rail installation kit since this type reduces drilling and overall installation time. Demco offers USA-made...
    view full answer...
  • Is Locking Adapter Plate Needed for Demco Hijacker Autoslide on 2006 Ford F-250
    The Demco Hijacker Autoslide Locking Plate # DM6095 referenced in your question works with just the Tri-Glide model of the Trailair Pin Boxes. It is required for the Tri-Glide design in particular because the 3 steel rods on this model act as rollers, letting the bottom jaw glide forward and back during towing. The locking plate is needed with the Demco Hijacker Autoslide # DM8550022 to prevent the king pin from rotating inside the trailer hitch. If your existing pin box is not the Tri...
    view full answer...
  • Recommended Auotslide Fifth Wheel Hitch for 2008 Ford F-250 Super Duty with 6-3/4 Foot Bed
    I do have a solution for you. You are correct that most sliding fifth wheel hitches are to be kept forward except while slowly making sharp turns. This is because you don't want the connection point of the trailer to be that far back in your truck bed, putting so much weight on your rear axle. The solution to this is an automatically sliding fifth wheel hitch like the Demco Hijacker. The Hijacker is available for below bed rails, # DM8550022, or above bed rails, # DM8550034. It works...
    view full answer...
  • Demco Hijacker 4 Pin Underbed System Measurement
    For your 2014 Ford F-250 short bed, it sounds like you have the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches # DM8551000. These holes will be 13-1/2 inches on center front to back and 29-5/8 inches on center side to side. I've attached a photo to assist. This is compatible with the Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed - 18,000 lbs # DM8550022. If that isn't the measurement, then send me...
    view full answer...
    Image 1 for
  • 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...
  • Will the Demco Underbed Rail Kit work with the 18,000 lb Capacity Sidewinder on my 2012 Ford F350
    With one small change absolutely. You just want to change the part # DM8550024 to the Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider part # DM8550022 this one is specifically designed and will work out great with the Underbed Rail and Installation Kit part # DM8551000 from Demco. It retains the 18,000 lb. capacity you originally inquired about it is the exact same thing just designed for Demcos's base rather than Ford's
    view full answer...
  • 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...
    view full answer...
  • Underbed Demco Fifth Wheel Autoslider Hitch and Rail Kit Recommendation
    The correct Demco underbed rail kit you'd need for your 2008 Ford F-250 short bed is the part # DM8551000. This is a custom fit kit designed for your truck specifically. Then when it comes time for an auto slider hitch you'd want the part # DM8550022 for an 18k hitch or part # DM8550037 for if you need a 21k hitch. For a 7-way relocation kit to put a 7-way in the bed of your truck you'd then want the Demco Kit part # DM8555002 and you'd be set.
    view full answer...
  • 5th Wheel Trailer Hitch that Slides Automatically for a 2012 Ford F-350 Short Bed
    I will be happy to help you out. For your 2012 Ford F-350, if it has the factory installed 5th wheel prep package with the 4 pucks in the bed I recommend the Demco HiJacker # DM8550038. This hitch will fit directly into the puck system. It offers 14 inches of travel and does slide automatically. I have linked a video review for you. If the truck does not have the factory prep package then you will also need an installation kit, # DM8551000, and you would use the HiJacker autoslide version...
    view full answer...
  • 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.
    view full answer...
  • 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...
    view full answer...
  • 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...
  • Under Bed Install Kit for a 2015 Ford F-350 and Demco 21K HiJacker Auto-Sliding 5th Wheel Hitch
    For your 2015 Ford F-350 and Demco 21K auto-sliding 5th wheel trailer hitch, # DM8550037, you will need under bed mount kit # DM8551000. I also recommend adding an in-bed 7-Way trailer connector to make hook up easier, # 41157. I have linked a video showing an example installation for you.
    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...
  • 5th Wheel Trailer hitch and Installation Kit for a 2016 Ford F-350 Short Bed without Prep Package
    Since your 2016 Ford F-350 short bed does not have the factory 5th wheel prep package you will first need an installation kit. I recommend the Demco under-bed kit # DM8551000. This kit mounts under the bed like the factory prep package. When the hitch is removed you will have a clear bed for cargo. For a compatible 5th wheel trailer hitch I recommend the Demco HiJacker # DM8550037. This hitch is rated for 21,000 pounds gross trailer weight and it slides automatically. You will not have...
    view full answer...


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Info for this part was:

Employee Lindsey S
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Expert Research:
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Employee Jeff D
Installed by:
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