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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 # DM8551006
Retail:$610.00
Our Price: $476.44
You Save: $133.56
Fifth Wheel Installation Kit

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Shipping Weight: 84 lbs
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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. 1-800-940-8924 to order Demco fifth wheel installation kit part number DM8551006 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. Fifth Wheel Installation Kit reviews from real customers.
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Demco Fifth Wheel Installation Kit - DM8551006

  • Below the Bed
  • Demco
  • Custom

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.


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
    • Brackets mount to the outside of your truck's frame rails - drilling is required
    • 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


8551006 Demco Hijacker UMS Under Bed Rail Frame Bracket Kit

Installation Details DM8551006 Installation instructions

This Product Fits The Following Vehicles

  • 2013 - 2018 Ram 3500 6-1/2 Foot Bed without OEM Prep Pkg
  • 2013 - 2018 Ram 3500 8 Foot Bed without OEM Prep Pkg
  • 2013 - 2014 Dodge Ram Pickup 3500 - 6-1/2 Foot Bed without OEM Prep Pkg
  • 2013 - 2014 Dodge Ram Pickup 3500 - 8 Foot Bed without OEM Prep Pkg




Customer Reviews

Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches - DM8551006

Average Customer Rating:  3.0 out of 5 stars   (1 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.

by:

Hitch looks great and functions great as well. Installation could’ve been smoother due to the installation instruction measurements being slightly off. Look at finding hole caps that are 3” instead of two and drilling the larger hole.


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

  • Underbed Fifth Wheel Hitch that Automatically Slides Recommendation for 2016 Ram 3500 Short Bed
    We have just what you would need. For an automatic sliding fifth wheel hitch that fits into underbed fifth wheel rails we have the Demco hitch part # DM855037. This hitch will autmatically slide back when making tight turns to give you the needed clearance. For an underbed rail kit to fit this hitch you would want the part # DM8551006 which is a custom fit rail kit for your truck.
    view full answer...
  • Demco Fifth Wheel Bracket Kit Recommendation that Doesnt Require Frame Drilling
    I have a no-drill Demco rail kit solution for your 2014 Ram 3500, but the # DM8551006 does require drilling of the frame. However, if you have the UMS hitch this would be your only option. The part # DM8552026 is another option for you to consider as it is a no-drill install. This will fit all fifth wheel hitches that are designed to fit industry standard rails.
    view full answer...
  • Demco Or Companion Underbed Hitch Recommendation for 2017 Ram 3500 Short Bed
    The install of the Demco Hijacker part # DM8550022 would be a little bit more involved the first time since the head locks to the pin box, but because of that it gives you a hitch that slides back automatically as you make tight turns. The hitch is easy to remove too as you can take it apart piece by piece so that you can lighten the load just like the Companion but overall I think you will be happier with the Demco. With it's underbed rail kit part # DM8551006 installed in the bed of...
    view full answer...
  • How Heavy is Demco Hijacker 5th Wheel Hitch for 2016 Ram 3500
    The Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider # DM8550037 has a shipping weight of just over 330 lbs though the head unit and base install separately. Still, it's a two-person job to remove it from the bed of your 2016 Ram 3500, even in a couple of pieces. Most fifth wheel hitches are going to be cumbersome, at the least, to regularly take in and out of the bed of your truck and the advantages of the Hijacker far outweigh its disadvantages. For starters, when you do take...
    view full answer...
  • 5th Wheel Trailer Hitch to Fit with a B&W Turnoverball Gooseneck Hitch in a 2014 Ram 3500
    The Demco Underbed Rail Kit # DM8551006 will not fit with the B&W Turnoverball, or any other gooseneck hitch, in your 2014 Ram 3500. To tow a fifth wheel trailer with the Turnoverball you can use the B&W Companion # BWRVK3400 which fits right into the gooseneck. They're specifically designed to work together. This is the sliding hitch which helps with turning clearance in a short bed truck like yours. I've linked a video of the Companion for you.
    view full answer...
  • Automatic Slider Fifth Wheel Hitch Recommendation for a 2016 Ram 3500 Short Bed
    I have a solution for you, but there isn't a way to install the Reese Elite Slider hitch part # RP30144 in the bed of a 2016 Ram. Ram uses their own hitch prep package that is similar to the Elite series hitches but since the pucks are spaced so far apart there is no way to get a standard Elite hitch to fit. I have a great towing solution for you though. I would recommend getting the 2016 Ram without the hitch prep package so that you can install the Demco Hijacker Auto Slide hitch part...
    view full answer...
  • Recommended 5th Wheel Rail Kit and Hitch for 2017 Ram 3500 without Bed
    For your 2017 Ram 3500, because you don't have a bed, I recommend the Demco Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches # DM8551006. This will use rails that don't attach to a bed, so they will work without it. Then, because this rail kit is specific to the 5th wheel hitch fit, you will need the Demco Hijacker UMS Double Pivot 5th Wheel Trailer Hitch - Single Jaw - Underbed - 21,000 lbs # DM8550032. If you will be adding a flatbed,...
    view full answer...
  • 2017 Ram Mega Cab Short Bed Fifth Wheel Trailer Hitch and Rail Kit Recommendation
    For your 2017 Ram 3500 short bed without the factory rail kit I have a great solution. The best towing setup we offer for short bed trucks is an automatic sliding fifth wheel hitch. This allows the hitch to slide back automatically as you make tight turns. For that you would want the Demco Hijacker part # DM8550022. Then for a set of underbed rails for the truck which will give you an open truck bed when not towing a fifth wheel trailer you would want the part # DM8551006.
    view full answer...
  • Best Fifth Wheel Slider Hitch Recommendation for 2013 Dodge Ram 3500 Short Bed
    Since you have a short bed 2013 Ram 3500 that means you need a slider fifth wheel hitch to allow you to have the needed clearance to make tight turns. Since slider hitches can be a bit of a hassle to operate everytime you need to make a tight turn we recommend the Demco Hijacker AutoSlide part # DM8550022 the most since it will slide for you automatically as you make a tight turn. This is also an underbed rail kit hitch so when the hitch is removed you will have an unrestricted truck bed....
    view full answer...
  • 5th Wheel Hitch to Fit 2018 Ram 3500 Short-Bed Pickup
    Currently Demco offers an under-bed rail kit for your 2018 Ram 3500 with 6-1/2-foot bed as long as it does not have the Rambox feature or the factory Air Suspension system. Under-bed rail kit # DM8551006 will allow installation of either of two Demco Hijacker Auto-Slide hitches, 18K model # DM8550022 or 21K model # DM8550037. There is no adapter offered to allow installing the Reese Elite in your Ram 3500. If your Ram 3500 happens to have the factory rail kit you can directly install...
    view full answer...
  • How to Install a Hijacker 16k 5th Wheel Hitch in a 2017 Ram 3500
    There's three options to mount a Demco Hijacker 16k 5th wheel hitch in the bed of your long bed 2017 Ram 3500. Which one you need will depend on the legs your 5th wheel hitch has and whether or not your Ram has the factory tow package. I have listed the options below: Industry Standard 5th Wheel Rails - B&W Custom Installation Kit w/ Base Rails item # BWRVK2605 Demco's Underbed System - Underbed Rail and Installation Kit for Demco UMS 5th Wheel Hitches item # DM8551006 Dodge OEM Puck...
    view full answer...
  • Under Bed Auto-Sliding 5th Wheel Trailer Hitch and Install Kit for a 2018 Ram 3500 Short Bed
    I have the perfect hitch and install kit for your 2018 Ram 3500 short bed. For the under bed installation kit use # DM8551006. Then for the auto-sliding hitch use Demco HiJacker 18K # DM8550022 or the 21K version, # DM8550037. I have linked videos on all three of these products for you. Please note: Installation kit does not fit vehicles with factory Air Suspension system I also recommend Demco 5th Wheel/Gooseneck 90-Degree Wiring Harness # DM8555002 to add a 7-Way connector in the bed...
    view full answer...
  • Recommended Universal 5th Wheel Mounting Brackets for a 2016 Ram 3500
    The Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches # DM8551006 for your 2016 Ram 3500 are designed for Demco 5th wheel hitches that use the Demco UMS (underbed mounting system) which is a unique mounting system only compatible with some of their hitches, like the 18K Hijacker # DM8550022. For universal rails that are compatible with 5th wheel hitches that use the industry standard system I recommend going with the Curt # C16430-204. This gives...
    view full answer...
  • Best Sliding 5th Wheel Hitch and Underbed Rail Kit for 2018 Ram 3500
    The best fifth wheel hitch for your 2018 Ram 3500 short bed is the Demco Hijacker Autoslide because you will never again need to get out of your truck just to make a turn and it can be mounted to underbed rails on your '18 Ram so your bed will be completely open if you choose to take the Hijacker out. The Hijacker fifth wheel hitch is available in two different towing capacities: 18,000 lbs at part # DM8550022 and 21,000 lbs at part # DM8550037; they will mount to the Underbed Rail and...
    view full answer...
    Image 1 for
  • Demco Hijacker vs. Pullrite SuperGlide for 2019 Ram 3500
    Easily the better option between the Demco Hijacker and Pullrite SuperGlide for your 2019 Ram 3500 is the Hijacker, which is what I would go with and highly recommend you do as well. The reasons are pretty straightforward, and starts with the elite jaw system of the Hijacker. It is a single-piece jaw that wraps totally around the king pin, and the connection is enhanced by a 3/4" solid steel bar that locks into place once the jaw is closed. This reinforced jaw system is what will give...
    view full answer...
  • 5th Wheel Hitch for 2018 Ram 3500
    Reese Elite Series 5th wheel hitch # RP30144 (which replaced the part 30085) is made only for the Ford OEM 5th wheel factory prep kit that uses under-bed rails. It will not work in a 2018 Ram. If the 2018 Ram 3500 has the factory 5th wheel prep then you can install a slider hitch from B&W, their 20K Companion model # BWRVK3670, which will drop right into the pucks in the bed. In a 2018 Ram short-bed without this factory feature you can still have an under-bed install using the Demco Hijacker...
    view full answer...
  • Recommended Under-Bed 5th Wheel Install Kit for a 2019 Ram 3500 with RamBox
    The only underbed fifth wheel install kit for a 2019 Ram 3500 is the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches part # DM8551006 which can then be used with the Hijacker UMS Double Pivot 5th Wheel Trailer Hitch part # DM8550032. The Demco Hijacker UMS is a great option which has a full wraparound style jaw that makes for an exceptional ride due to the reduced chucking and jarring. Please note, because of the RamBox feature you must...
    view full answer...
  • Recommended 5th Wheel Trailer Hitch for 2018 Ram 3500
    We do have a large selection of great fifth wheel hitches that will work well on your 2018 Ram 3500 to tow your DRV Mobile Suite trailer. If your Ram does not have the factory rail kit and has a 6-1/2 foot bed, I recommend a sliding hitch like the Demco Hijacker Autoslide # DM8550037. This is an excellent hitch that will actually slide automatically as you drive to give you 14 inches of additional clearance for tight turns with your short bed truck. It has a 21,000 pound gross towing capacity...
    view full answer...
  • How to Tow 5th Wheel Trailer with 2016 Ram 3500 and Demco UMS Rails
    Yes, you can definitely use the Underbed Rail and Installation Kit # DM8551006 on your 2016 Ram 3500 along with the UMS Series Gooseneck Trailer Hitch # DM5988 and Convert-A-Ball Adapter w/ Offset # CAB-C5GX1216. Since you have a short bed I do recommend checking out our clearance formula and checking your measurements to make sure this setup will give you clearance to make turns without hitting your truck cab: (A + B) - C = Clearance A = Distance from center of fifth wheel hitch jaw...
    view full answer...
  • Fifth Wheel Hitch and Tonneau Cover Recommendation for 2017 Ram 3500 with Short Bed
    For your 2017 Ram 3500 6-1/2 Foot Bed without Factory Rail Kit you'll need a slider hitch to allow you to make tight turns without cab interference. My favorite slider hitches are the ones that automatically slide as you make tight turns as that saves you the hassle of getting out and activating the slider every time it's needed. For that I would recommend the Demco Hijacker part # DM8550037 and the install rail kit part # DM8551006. This is an underbed rail kit too which means when you...
    view full answer...
  • 5th Wheel Trailer Hitch and Install Kit for a 2016 Ram 3500 Short Bed and No Prep Package
    Yes, you can install an under-bed 5th wheel installation kit. For your 2016 Ram 3500 short bed without the factory prep package I recommend Demco install kit # DM8551006. When the hitch is removed the bed will be clear for cargo. For a 5th wheel trailer hitch that fits this kit I recommend the Demco HiJacker auto-sliding 5th wheel trailer hitch # DM8550037. This hitch is rated for 21,000 pounds gross trailer weight. It slides automatically so you will not have to get in and out of the...
    view full answer...
  • Is the 21K Demco Hijacker UMS Compatible with a 2019 Chevy Silverado 3500
    For the Demco Hijacker UMS Double Pivot 5th Wheel Trailer Hitch # DM8550032 to fit your 2019 Chevy Silverado 3500 you actually need the specific Underbed Rail and Installation Kit # DM8551010 from Demco. If you have the OEM prep package on your Chevy and you are wanting to use a similar 21K Demco 5th wheel hitch then you would need to use the Demco Hijacker Premier Series Double Pivot 5th Wheel Trailer Hitch # DM6076P-21K along with the 5th Wheel Rail Adapter # DM6206. These 5th wheel...
    view full answer...
  • 5th Wheel and Conventional Towing Weight Capacities for 2018 Ram 3500
    The 2018 Ram 3500 with Cummins Diesel is dependent on the axle ratio, the cab, and the box length. I've attached the chart to assist with each of these. The number in the parenthesis for each of them is the 5th wheel towing capacity and the other number is for the trailer hitch receiver below the bumper. If you are looking for a trailer hitch receiver, I have linked the page to your options to assist. Assuming you are looking for 5th wheel components, if you have the factory tow package,...
    view full answer...
    Image 1 for
  • 5th Wheel Hitch Options for 2018 Ram 3500 Pickup with 6-1/2-Foot Bed
    Reese Goosebox 5th wheel trailer couplers do not provide extended turning clearance like what comes from use of a slider hitch or a Sidewinder pivoting pin box. What the Goosebox DOES allow is using a gooseneck trailer ball to tow a 5th wheel trailer. In your 2018 Ram 3500 6-1/2-foot short-bed pickup you can use a slider hitch and either industry-standard above-bed base rails or an under-bed kit. For example, the Demco Hijacker 21K hitch # DM8550037, which offers a whopping 14-inches of...
    view full answer...

Do you have a question about this Fifth Wheel Installation Kit?


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 Jeff D
Installed by:
Jeff D
Employee Jacob T
Video Edited:
Jacob T
Employee Laura H
Updated by:
Laura H
Employee Wilson B
Updated by:
Wilson B
Employee Amanda M
Updated by:
Amanda M
Employee Kristina F
Updated by:
Kristina F
Employee Justice A
Updated by:
Justice A
Employee Chelsea B
Written by:
Chelsea B
Employee Chris R
Video by:
Chris R
Employee Andrew S
Test Fit:
Andrew S

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