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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 # DM8551009
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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 DM8551009 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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2018 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


8551009 Demco Hijacker UMS Under Bed Rail Frame Bracket Kit

Installation Details DM8551009 Installation instructions


Customer Reviews

Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches - DM8551009

Average Customer Rating:  3.7 out of 5 stars   (13 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:

Good kit. All the parts were sturdy and well made. Took my truck in to a local installer and he completed the installation in about 1/2 of a day. You should be aware that the installation involves unbolting the truck bed from the frame and that makes DIY a major undertaking. Unless you have the tools, equipment and skills you should plan on using a professional installer. With this kit I can remove my hitch and the truck bed is open and uncluttered for every day use. Only evidence of the hitch are the four flush plastic caps on the bed.


Comments
Still good after one year. My hitch is easy to install and remove with the help of a modified engine hoist. The truck bed remains just that, a truck bed for hauling crap around.
Sheryl - 02/21/2022


by:
2017 Ford F-250 Super Duty

Easy in stall, Had my bed liner sprayed in and was afraid of scraping it taking out the hitch. Have had no problems so far even though I do it on my own. Its heavy but light enough for me to move to the back of the bed and take out with a floor hoist.


Comments
It did take work too install. The bed did have to be raised up but it wasnt a big deal. I do wish they had caps that fit better in the holes because the rails do sit flush with the bottom of teh bed. Rubber s moght be better to grip in.
kenneth r - 02/06/2021


by:

Moderate install. Follow the instructions Don't be a man and think you can do it without them you will waste time. Read the instructions in full 1st.




by:

This rail system is certainly robust and I’m not concerned about it carrying the load of the fifth wheel at all. It is a quality product and seems to be made well. I installed this myself and it should be a relatively easy install; however, it was a huge pain. The rails install under the bed of my 2020 F-250 shortbed at the exact location where the truck frame has a bend in it. For this reason, the locking pins from the auto slide hitch above the bed couldn’t reach the under bed rail receiver holes (there was too much space since the frame rails slid down the bend in the frame). I couldn’t have installed this system by myself. With the help of a buddy, we were able to adjust the above bed hitch locking pins while one person was under the truck holding up the frame rails so they were snug with the bottom of the bed. This allowed the pins to properly drop into the frame rail receiver holes and lock the rails up against the bottom of the bed. In hindsight I could have held the rails in position by attaching them to the frame brackets first but that’s not how the instructions were laid out. This was my first fifth wheel hitch install so I guess I learned something to make my next install easier.




by:
2018 Ford F-350 Super Duty

Have this installed in my 18 F350 SRW and it works ok. Sometimes the latches bind when removing the hitch because it shifts slightly when towing.

Installation was a pain. I had to remove all of the bolts holding the bed on, then raise the bed about 3" to get the rails in. Also, the rails sit directly up against the bottom of the bed so there's no way to install the hole covers when you have the hitch removed.




by:
2017 Ford F-350 Super Duty

Not so much the product, I'm sure it's great. But part number 60050 is apparently to similar the the part I received, part 6050. Paid extra for faster shipping on the original order. Because wrong parts were sent, we are returning it all. We had to locally source an entirely different hitch because we needed to install on a new truck that day. By locally sourcing, I mean drive 2 1/2 hours one way to get an above bed hitch and mounting system. Now I have a bunch of holes drilled in the bed of my truck that I didn't want and the customer service was horrible.




by:
Dodge Durango

2019 Durango 5th wheel hitch install kit for my customers new truck

Always RV
Mesa AZ




by:

Great return response




by:

The Delivery was missing parts. I called customers service they replaced and delivery next days .




by:
2018 Ford F-350 Super Duty




by:




by:




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



  • Installing An Underbed Rail Installation Kit For Demco Hijacker UMS 5th Wheel And Gooseneck Trailer
    Yes, to install the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches Item # DM8551009 you will need to lift the bed approximately 2" to get the rails in between the frame and the bed.
    view full answer...
  • Best Sliding Fifth Wheel Hitch Recommendation and Rail Kit for 2017 Ford F-350
    The setup I would recommend is the Demco Hijacker Auto Slide part # DM8550022 with the rail kit part # DM8551009 for your 2017 Ford F-350 without the factory tow package. This is a slider hitch that will automatically slide back as you make tight turns which is a very nice feature as getting out and activating a slider mechanism can be a hassle. Especially in inclement weather. The rail kit mentioned is an underbed kit so your bed will be clean and free of large rails when you remove...
    view full answer...
  • Can Demco Hijacker Autoslide 5th Wheel Hitch be Used in Long Bed Truck
    While sliding fifth wheel hitches aren't necessary for long bed trucks, there is no reason you cannot use your existing Demco Hijacker Autoslide 5th Wheel Trailer Hitch # DM8550022 in your new 2017 Ford F-450. You will not have any issues when it comes to the sliding mechanism and travel of the hitch. If your F-450 does not have the factory rail kit, you can use the Demco Underbed Rail and Installation Kit # DM8551009. This kit is custom-fit for this truck and will allow you to mount...
    view full answer...
  • Underbed Rail Kit Recommendation for 2017 Ford F-350 for Demco Hijacker Hitch
    The correct Demco underbed style rail kit for your 2017 Ford F-350 short bed is the part # DM8551009 which is a custom fit for your truck and is also a fit with your Demco hijacker hitch # DM8550022 as well.
    view full answer...
  • Recommended Fifth Wheel Hitch and Underbed Rails for 2017 Ford F-250 With Long Bed
    I'd be happy to help you when it comes to fifth wheel hitches. Essentially, to mount a fifth wheel hitch you need rails, and there are two types of rails: in-bed and underbed. The in-bed rails will be, as the name suggests, installed and exposed on top of your truck bed so you when you remove the fifth wheel hitch they would still be present. Underbed rails will be hidden and allow for complete bed access when your fifth wheel hitch is removed. Some trucks have an optional package that...
    view full answer...
  • Best Auto Slide Hitch For 2020 Ford F-250 Super Duty That Doesn't Require Rails in the Bed
    I have a great option for you that doesn't require rails in the bed. I recommend the Demco 21K Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider part # DM8550037 and the under bed rails part # DM8551009 for the 2020 Ford F-250 Super Duty. The Hijacker is one of the easiest to use sliding fifth wheel hitches on the market because you don't have to get out of your truck to adjust the slider when you make turns which can become inconvenient especially in city traffic or bad weather. It...
    view full answer...
  • Demco UMS Underbed Hitch Recommendation for 2018 Ford F-350 Super Duty
    The Demco UMS Underbed Rail Kit part # DM8551009 is a fit for your 2018 Ford F-350 long bed and will give you an underbed style of rails for a fifth wheel hitch. The UMS Fifth Wheel Hitch part # DM8550032 is a confirmed fit for this rail system so it would also work well. This hitch is compatible with a Mor Ryde pin box too.
    view full answer...
  • Can Demco Gooseneck Adapter # DM5988 be Used with Underbed Demco Rails DM8551009
    Since you have a set of Underbed Demco Rails part # DM8551009 installed in your truck you can use the gooseneck adapter part # DM5988 that you referenced.
    view full answer...
  • Demco Hijacker Trailer Hitch w/ Slider # DM8550022 Refit to Newer Truck
    The Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider, # DM8550022 is specially designed to fit a Demco UMS custom underbed mounting kits sold separately from the hitch. You would need to identify exactly what make model for me to list the specific components. The Underbed Rail and Installation Kit for Demco Hijacker, # DM8551009 fits later model Ford F-350's.
    view full answer...
  • Recommended 5th Wheel Hitch with Underbed Rail Kit for 2017 Ford F-250 Short Bed
    For your 2017 Ford F-250 4WD with a short bed and without the factory rail kit, I recommend looking at the Demco Hijacker Autoslide # DM8550022, along with the Underbed Rail and Installation Kit # DM8551009. This is an excellent 5th Wheel Hitch that features an 18,000 pound towing capacity and an automatic slider that will provide 14 inches of travel for making sharp turns in your short bed truck. It also has a premium wraparound, single-piece jaw for a secure connection with the trailer...
    view full answer...
  • Recommended Demco Hijacker Autoslide with Underbed Rail Kit for 2017 Ford F-250 without Prep Package
    The Demco Hijacker Autoslide # DM8550024 referenced in your question is designed specifically to mount to the factory 5th wheel pucks on a Ford truck. It will not work on your 2017 Ford F-250 that doesn't have the factory prep package. The Ford pucks have a different configuration than the Demco Underbed Rail System that is used for the standard Hijacker models. The Demco Hijacker Autoslide # DM8550022 that you also mentioned is what you need for your Ford F-250 along with the Demco Underbed...
    view full answer...
  • Under Bed Auto Sliding Fifth Wheel Hitch Options for 2020 Ford F-250
    We do have a good mounting option to install a fifth wheel hitch in your truck bed without needing the rails that sit in the truck bed. Demco actually has an under-bed mounting kit, part # DM8551009 which would be used along with the # DM8550034 Hijacker Autoslide 18K rated hitch. When the hitch is removed, there will only be 4 holes in the truck bed, similar to the OEM puck system. To provide a 7-way tailer connector in the truck bed, you'd need the # DM8555002 wiring harness. I've...
    view full answer...
  • Underbed Fifth Wheel Hitch and Rail Kit Recommendation for 2017 Ford F-250
    We have the Demco underbed rail kits that fit your 2017 Ford F-250 like the part # DM8551009. With this kit installed you could use their 21k Demco hitch part # DM8550032 if you have a long bed or the auto slider part # DM8550022 if you have a short bed. The Demco hitches are USA made hitches that will work great for your application.
    view full answer...
  • Comparing the Demco Hijacker Autoslide DM8550038 and DM8550037 for a Ford Super Duty
    The Demco Hijacker Autoslide 5th Wheel Hitch part # DM8550038 and the Demco Hijacker Autoslide 5th Wheel Hitch part # DM8550037 are the same hitch. The only difference is the side plates they come with, the former has side plates for the puck system on a Ford Super Duty whereas the latter has side plates to mount with Demco's underbed pucks which are different from the puck system on a Ford Super Duty. If you don't have the Ford puck system then you will need the Underbed Rail and Installation...
    view full answer...
  • Will the 13K Demco Autoslide # DM8550041 Work with a 2018 Ford F-250 6-3/4' Bed
    Yes, the Demco Hijacker Autoslide 5th Wheel Trailer Hitch # DM8550041 is compatible with your 2018 Ford F-250 with a 6-3/4' bed. This hitch actually installs in the Demco Underbed Rail and Installation Kit # DM8551009 instead of a traditional "OEM prep package". If you don't already have a 7-Way in the bed of your F-250 then I also recommend the Demco # DM8555002 which help make connecting and disconnecting the wiring in your pickup much easier.
    view full answer...
  • Demco Hijacker Autoslide to Fit 2019 Ford F-350 with Factory 5th Wheel Prep Package
    The Demco Hijacker Autoslide fifth wheel hitch you asked about, part # DM8550022, actually fits into an aftermarket underbed kit, part # DM8551009. It doesn't fit the OEM puck system you have in your new 2019 Ford F-350. Instead you want part # DM8550024 that does fit right onto the pucks. It's basically the same hitch except for how it mounts into the truck. I've linked a video of it going into a 2014 F-350. It's the same puck system as what you have.
    view full answer...
  • Correct Demco Hijacker Autoslide 5th Wheel Trailer Hitch For A 2017 Ford F-250
    The Demco Hijacker Autoslide 5th Wheel Hitch part # DM8550038 is specifically designed to fit Ford trucks that were equipped with the factory prep package and cannot be installed unless you have this package or have the dealer install it. I do however, have the same 5th wheel hitch in the Demco Hijacker Autoslide 5th Wheel Trailer Hitch part # DM8550037 that is compatible with your 2017 Ford F-250 Super Duty using the Demco Hijacker Premier Series Below-Bed Base Rails and Custom Installation...
    view full answer...
  • Under Bed 5th Wheel Rail Kit and AutoSlider Hitch Compatible with 2019 Ford F-350 Without OEM Pucks
    The Under-Bed Rail and Installation Kit for Reese Elite Series 5th Wheel Trailer Hitches #30068 was discontinued and is only compatible with commercial 34 inch frames, so it won't fit your 2019 Ford F-350. I reached out to Reese and they don't currently have a model compatible with the 2017-2019 model trucks. I do have an option for you that gives you the under bed rails and the automatic slider you are seeking, but you won't have the pucks like the factory option. I attached a photo...
    view full answer...
    Image 1 for
  • Will Bed of 2019 Ford F250 Need to Be Raised to Fit Demco DM8551009 Underbed Hitch Mounting Rails
    For your 2019 Ford F-250, Demco offers the Hijacker Autoslide in either an 18K version as part # DM8550022 or a 21K version as part # DM8550037. You'd also need the # DM8551009 under-bed rail kit. According to the installation instructions that I've linked for you, you won't need to completely remove the bed, but you will need to loosen the bolts that hold the bed on in order to slide the rails into place. This is especially true because you'll place the included vinyl sheets on top of...
    view full answer...
  • How To Gain Vertical Clearance On A 5th Wheel Hitch And Pin Box That Is Hitting The Tailgate
    If you have your Trailair Flex Air 5th Wheel Pin Box - Lippert 1621 - 18K # LC328492 adjusted to its lowest position and the 5th wheel hitch is adjusted all the way up and you still don't have the necessary clearance, then you will need to look into a new 5th wheel hitch that will be compatible with your setup. The Demco Hijacker UMS Double Pivot 5th Wheel Hitch # DM8550033 fits your 2021 Ford F-350 if it has the factory puck system. This has a hitch height: 16" - 19", which is the tallest...
    view full answer...
  • What is the Difference Between an Under-Bed and Above-Bed 5th Wheel Base Rail Kit 2018 Ford F-350
    In order to install the Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider part # DM8550035 for above-bed base rail kits or part # DM8550037 for below-bed base rail kits on your 2018 Ford F-350 Super Duty you will need a set of 5th wheel base rails. We currently have two different sets of base rail kits for your truck; under-bed and above-bed. The above-bed base rail kit like the Demco Hijacker Premier Series Above-Bed Base Rails and Custom Installation Kit for 5th Wheel Hitches...
    view full answer...
  • Gooseneck Hitch For Demco Hijacker UMS Series Rails Installed on a 2018 Ford F-350 Super Duty.
    Since you have the Underbed Rail and Installation Kit for Demco Hijacker UMS # DM8551009 on your 2018 Ford F-350 Lariat you will need the Demco Hijacker UMS Series Gooseneck Trailer Hitch # DM5988. This hitch will drop right into your rails and it has a 25,000lb trailer weight capacity, with the tongue weight capacity being 6,250lbs. The Demco Hijacker SL Series Gooseneck Trailer Hitch # DM5992 will only work with SL rail systems like the Custom Installation Kit w/ Base Rails for Demco...
    view full answer...
  • Under Bed Installation Kit and 5th Wheel Hitch Recommendations for a 2017 Ford F-350
    There are under bed installation kits available for the 2017 Ford F-350 even if Reese hasn't released one just yet (4/4/2017). I recommend the Demco kit # DM8551009. For a hitch it will depend on if you have a short or long bed. For a short bed I recommend the HiJacker # DM8550022 for an 18K or # DM8550037 for a 21K. Both of these hitches slide automatically and have 14 inches of travel. I have linked a video review of the 21K version for you. If you have a long bed then you will not...
    view full answer...
  • 5th Wheel Hitch Recommendation for 2020 Ford F350 Short Bed
    From you description, you're wanting an easy to use hitch that provides a good level of ride quality that won't transfer all the road shock from the 5th wheel to the tow vehicle. I'd recommend the Demco Hijacker Autoslide, which is available in an 18K capacity model as part # DM8550022 or a 21K model as part # DM8550037. These hitches are compatible with the Demco # DM8551009 under-bed rail system that will leave your bed completely unobstructed once the hitch is removed. The hitch...
    view full answer...


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Info for this part was:

Employee Mike L
Expert Research:
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Expert Research:
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Edited by:
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Employee Jeff D
Installed by:
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Updated by:
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