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

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

Item # DM8551000
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Fifth Wheel Installation Kit

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Demco Custom - DM8551000
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Custom, underbed rail kit allows for uninhibited use of your truck bed once your hitch is removed. Works with Hijacker Underbed Mount Series (UMS) fifth-wheel and gooseneck hitches. No-drill frame brackets offer a simple installation. Call 800-298-8924 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 Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches. Fifth Wheel Installation Kit reviews from real customers.
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  • Q & A (53)
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2013 Ford F-250 and F-350 Super Duty - Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches

  • Demco
  • Below the Bed
  • Custom

Custom, underbed rail kit allows for uninhibited use of your truck bed once your hitch is removed. Works with Hijacker 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 Hijacker 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 Hijacker Underbed Mount Series (UMS) 5th-wheel and gooseneck trailer hitches
  • 5-Year limited warranty


8551000 Demco High Jacker UMS Under Bed Rail Frame Bracket Kit

Installation Details DM8551000 Installation instructions


Customer Reviews

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

Average Customer Rating:  4.6 out of 5 stars   (14 Customer Reviews)

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

- DM8551000
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. 809559



- DM8551000
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. 674456



- DM8551000
by:

Great design. Installation wasn't bad at all (plan on buying a carbide drill bit). Hole plugs just cheap plastic. 619216



- DM8551000
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! 605570


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

68868

- DM8551000
by:
1999 Ford F-250 and F-350 Super Duty

nice product fit was good. prompt ship ping. 591295



- DM8551000
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 575825



- DM8551000
by:
2008 Ford F-250 and F-350 Super Duty

Great product, drill 4 holes and you are done, simple. 549497



- DM8551000
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. 519980



- DM8551000
by:

worked perfect.no drilling! well worth buying this instead of the universal kit. and no rails in the bed! 485472


Comments
great!
Buddy R - 03/24/2019

50937

- DM8551000
by:

Was easy to install with very few tools. 466135



- DM8551000
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 460171



- DM8551000
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. 424052



- DM8551000
by:

The under bed mount for the demco auto slide was easy to install with easy instructions and works great 403179


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

40702

- DM8551000
by:
2012 Ford F-250 and F-350 Super Duty

Excellent product, it is fairly easy to install. 318260


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Ask the Experts about this Demco Fifth Wheel Installation Kit

  • 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...
  • 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...
  • Under Bed 5th Wheel Installation Kit for 2008 Ford F-250 Short Bed with Air Bag Helper Springs
    Because of where the air bag brackets mount on the frame of your 2008 Ford F-250 the only 5th wheel installation kit that would work is the universal kit # RP30035. This is an above the bed kit though. None of the under bed mounts will work because of the air bag brackets. If an under bed kit is a must then you can install a different air bag system, # F2550. Then you can use Demco under bed installation kit # DM8551000. This installation kit is compatible with Demco 5th wheel hitch...
    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...
  • 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...
  • 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...
  • 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...
    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...
  • Recommended 5th Wheel Installation Kit and Slider Hitch for 2017 Ram 2500 with 6-1/2-Foot Bed
    We can help you with a 5th wheel hitch install kit to allow use of a slider hitch in your 2017 Ram 2500 with 6-1/2-foot bed and without the factory rail kit. The simplest above-bed base rail installation comes with a custom-fit type kit. Custom kits reduce the drilling time required and make the overall install a good bit easier. Since they are all made to the same industry-standard I suggest the lowest-cost option, Pro Series base rail kit # RP50054-58. These rails will accept any industry-standard...
    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...
    view full answer...
  • Best Sliding 5th Wheel Hitch Options for a 2015 Ford F-250 Super Duty
    It is recommended to get a sliding 5th wheel hitch if you have a truck with a bed that is shorter than 8 feet but longer than 6 feet. The reason for this is so that you don't hit the cab of your truck with your trailer when you are making tight turns. I do have a few recommendations for your 2015 Ford F-250 with a short bed. As far as the 15K Reese slider goes, I can't say that we have heard anything. The only thing that I can think of is if it was an older model that uses the square...
    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...
  • Recommended Sliding Fifth Wheel Hitch For 2016 Ford F-250 With Short Bed
    There are a couple ways you can go for a towing setup. If you want full access of your 2016 F-250 truck bed when you are not towing I recommend an underbed rail system for your fifth wheel hitch like the Demco, part # DM8551000. I then recommend a sliding hitch like part # DM8550022. This hitch has 14-inches of front to back travel so you can make sharper turns. The great thing about this hitch is that you do not have to exit the truck when executing turns because this hitch automatically...
    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...
    view full answer...
  • Operation and Compatibility of Demco Autoslide 5th Wheel Hitch with Air Lift Rear Air Bag Kit
    The rack-and-pinion slider mechanism in the Demco Hijacker Autoslide 5th Wheel Trailer Hitch # DM8550022 does work in both forward and reverse directions. Once the pin box causes the hitch head to turn past about 15-degrees the autoslide mechanism engages and slides the head unit rearward for better turning clearance. In your 2016 Ford F-250 short bed without factory rail kit you can use Demco installation kit # DM8551000 and for a wiring harness part # DM8555002 which plugs right in...
    view full answer...
  • 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...
    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...
  • 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...
  • 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...
    view full answer...
  • Recommended 5th Wheel For 2010 Ford F-250 Super Duty Towing a 39 Foot 5th Wheel Trailer
    I can help you decide which 5th wheel is better for your 2010 Ford F-250 with a 6-3/4 bed. The Demco # DM6076P-UL-21K and the Reese # RP30084 are very comparable in weight capacity and height adjustments. If it were me I would go with the Demco # DM6076P-UL-21K, because of its slightly higher capacity and the quieter ride, due to the additional dampeners. You will want to determine the total loaded weight of your 39 foot trailer and make sure it doesn't exceed the weight of the hitch...
    view full answer...
  • Fifth Wheel Hitch Recommendations for 2002 Ford F250 Short Bed
    If your truck has the factory tow/prep package, there are hitches available that would drop right into the 4 pucks installed in your truck bed. Due to the short bed, you'd need a sliding hitch like the Demco Hijacker Autoslide 21K, part # DM8550038. The Autoslide differs from regular sliding hitches in that you won't need to exit the vehicle to actuate the sliding mechanism. The hitch does that automatically. If you do not have the factory tow/prep package, you can still use a different...
    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...
    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...
    view full answer...
  • 5th Wheel Trailer Hitch and Install Kit Recommendations for a 2015 Ford F-250 Short Bed
    Since your 2015 Ford F-250 has the short bed I strongly recommend using a 5th wheel installation kit and hitch and not using an adapter in a gooseneck hitch. The reason is that will the short bed truck you will want as much clearance as you can get when turning so that the trailer and truck do not collide. Adapters do not offer much additional clearance. Since you like the clean look of the gooseneck I have an excellent solution for you. I recommend the B&W system using installation...
    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...
    view full answer...
  • Will Air Bags Work with the Underbed Rail and Installation Kit for Demco Hijacker 2008 Ford F-350
    The Demco Hijacker Autoslide 5th Wheel Trailer Hitch part # DM8550022 and Underbed Rail and Installation Kit for Demco Hijacker part # DM8551000 for your 2008 Ford F-350 will only work with Firestone air bag kits. Therefore, if you have the Firestone Ride-Rite Air Helper Springs part # F2550 yes, they will work with the 5th wheel kit but if you have the Air Lift LoadLifter 5000 part # AL57212 no, they will not work with the 5th wheel kit. The Firestone kit listed above is the only option...
    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...
  • Recommended Automatic Sliding Fifth Wheel Trailer Hitch on 2016 Ford F-250 Short Bed
    For an automatic sliding fifth wheel hitch I recommend the Demco Hijacker Autoslide # DM8550035 with the custom install kit # DM8552000-71. Or if you prefer a below bed option, # DM8550037 with custom install kit # DM8551000. They're both designed specifically to work on short bed trucks and are confirmed to fit your 2016 Ford F-250 Super Duty with the 6-3/4 foot bed and no factory rail kit. They provide 14 inches of movement to help with turning clearance and the gross trailer weight...
    view full answer...




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Info for this part was:

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

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