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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 # DM8551010
Retail:$698.99
Our Price: $495.79
You Save: $203.20
Fifth Wheel Installation Kit

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Shipping Weight: 76 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. No-drill frame brackets offer a simple installation. 1-800-940-8924 to order Demco fifth wheel installation kit part number DM8551010 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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  • Reviews (14)
  • Q & A (0)
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Demco Fifth Wheel Installation Kit - DM8551010

  • 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. 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


8551010 Demco Hijacker UMS Under Bed Rail Frame Bracket Kit

Replaces Demco DM8551002 and DM8551003

Installation Details DM8551010 Installation instructions

This Product Fits The Following Vehicles




Customer Satisfaction Score:


Customer Reviews

Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches - DM8551010

Average Customer Rating:  3.9 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 Underbed Mount Series (UMS) fifth-wheel and gooseneck hitches. No-drill frame brackets offer a simple installation.

by:

This product is nice but doesn’t line up with OEM placement of pucks.

Etrailer Expert

Sierra K.

8/23/2021

That is because this product only fits vehicles without The OEM Prep Package. You want something like this: Item # DM6194.



by:

The instructions provided with the hitch were very detailed and provided enough information for me to install it myself. I love having the mounting rails below the bed. the auto slide worked flawlessly. For the winter I left the hitch coupled with the trailer to keep my bed clear.



by:

Merchandise arrived in good condition. Nothing missing. The shipping carton was in terrible condition. It was torn open from shipping, however nothing was missing or damaged . The product will fill my needs to replace the above bed rails that don't leave a clean bed when fifth wheel is removed. This will fill the bill. Thanks to Etrailer this will work perfectly for my Demco hijacker fifth wheel. Shipment was quick delivery.



by:

Kit made for my rig and fit as described. Installation a little on the difficult side for your typical DIY'er.

Kirk C.

7/26/2020

The under bed kit is the best. Having the truck bed useful when not traveling is great. I use a small electric hoist and casters for lifting and moving so the weigh is no problem. Installation was a little on the difficult side but any experienced DIYer can handle it.



by:
2017 GMC Sierra 2500

First package was destroyed in shipping, all hardware was missing, called etrailer forgot her name ( sorry ) very polite. she ordered all the correct hardware needed and had it shipped out. Except for the shipping was very pleased with etrailer.



by:
2018 Chevrolet Silverado 3500

Once I mounted everything and figured out I had to switch passenger and drivers brackets everything was fine it worked out ok



by:

It arrived in two days. Great delivery.



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2012 Chevrolet Silverado



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14
14

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

  • Can Demco SL Series 5th Wheel Hitch be Used on 2018 GMC Sierra with Factory Pucks
    I spoke with my contact at Demco and unfortunately there is not a good way to convert the SL Series 5th Wheel Hitches like # DM6076SL-16K, nor is there an adapter available, that will allow it to attach to the factory pucks on your 2018 GMC Sierra 2500. Your only option is to go with a brand new hitch that is designed to mount to those pucks. For this I highly recommend the Curt A16 Slider # C16668 if your Sierra has the 6-1/2 foot bed or the fixed A16 # C16520-16025 if you have the 8...
    view full answer...
  • Slider Kit Availability For A Reese 22K Series 5th Wheel Hitch
    We do offer slider kits for Reese hitches like the Reese Square Tube Slider for 5th Wheel Trailer Hitch # RP30048 that works with 15K, 16K, or 20K Reese 5th wheel hitches. However, unfortunately your Reese 22K Fifth Wheel Hitch # 30034 is not a compatible hitch for these sliders. If you need a slider hitch for your Silverado, I recommend the Demco Hijacker Autoslide 5th Wheel Hitch # DM8550037 with the rail kit # DM8551010. This awesome hitch is capable of towing a maximum of 21,000 lbs,...
    view full answer...
  • Recommended 5th Wheel Hitch for 2019 Chevy 2500HD Short Bed without OEM Pucks
    I recommend using the Demco Hijacker Autoslide # DM8550034 on your 2019 Chevy 2500 without the OEM prep package since the slider automatically activates, so there's no getting out of the vehicle required each time you may need to make a tight turn. I also really like that this gives you an under-bed mounting kit with the # DM8551010 so you'll still have a completely clear truck bed when you're not towing your 5th wheel. This hitch has an 18,000-lbs capacity but if you're in need of a larger...
    view full answer...
  • Weight of Demco Hijacker Autoslide 5th Wheel Hitch Underbed Mount for 2016 GMC Sierra 2500
    The Demco Hijacker Autoslide 5th Wheel Trailer Hitch with Slider - Underbed Mount # DM8550022 has a shipping weight of 300 lbs, so when you subtract its shipping material it comes in at approximately 290 lbs. This hitch is a fit for your 2016 GMC Sierra 2500 when mounted in the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches # DM8551010. I have added a link to an installation video of those rails in an '18 Sierra 2500 for you to check...
    view full answer...
  • Can the Demco Hijacker 5th Wheel Hitch Be Used W/ a 2014 Chevrolet Silverado 2500 W/ OEM Pucks
    Hey Nick, so it looks like the only way you're going to be able to use your Demco Autoslide 5th Wheel Trailer Hitch w/ Slider # DM8550037 with your 2014 Chevy Silverado is by using the custom underbed mounting kit # DM8551010. This is one of the few hitches that does not use ISR or an OEM puck system to install so you'd have to use their install kit.
    view full answer...
  • Best Fifth Wheel Hitch Recommendation for 2017 Chevrolet Silverado 3500 Short Bed
    For your 2017 Chevy Silverado 3500 with a 6-1/2 foot bed the best fifth wheel hitch setup we have is the Demco Hijacker Auto Slide part # DM8550037. Since you have a short bed truck you have to have a slider hitch to allow you to make tight turns. Since most slider hitches make you get out and manually operate them the benefit to the Demco is that it does this automatically as you turn saving you the hassle. Then for a rail kit you'd want the part # DM8551010 which is a custom fit underbed...
    view full answer...
  • Will Demco Hijacker Fifth Wheel Hitch Fit with Firestone Air Suspension in a 2015 GMC Sierra 2500
    The Firestone Ride Rite system part # F2709 that you installed on your 2015 GMC Sierra 2500 is compatible with fifth wheel rail kits so it would allow you to install a fifth wheel hitch like the Demco Part # DM8550037 that you referenced. The correct rail kit you would need to install this hitch is the part # DM8551010 which has been confirmed as a fit for your truck. The Demco Hijacker hitch you are interested in is a great hitch for towing a short bed truck as it automatically slides...
    view full answer...
  • Solution to Use Curt Slider Hitch on 2019 GMC Sierra 2500 Short Bed Without OEM Prep Package
    I may have a solution for you, but there is not a solution for you to add an aftermarket OEM style prep package for your 2019 Sierra 2500 that would be compatible with the Curt # C16023, which is only compatible with the factory prep package. For these reasons you will need to install a different 5th wheel installation rail kit to use your existing Curt sliding hitch. The rails you'll want to use, which are a custom fit for the 2019 Sierra 2500, are the Curt # C16411-204. This will give...
    view full answer...
  • Will Demco Hijacker Autoslide Work With B&W Turnovernall On 2016 GMC Sierra 2500
    The Demco Hijacker Autoslide 5th Wheel Trailer Hitch won't work with a B&W Turnovernall Gooseneck Trailer Hitch. The issue is not that they don't offer a way to attach the two but rather that the singular connection point cannot withstand the stress of an auto-sliding fifth wheel hitch. Therefore, you can either use the B&W Companion Slider Gooseneck-to-5th-Wheel Trailer Hitch Adapter part # BWRVK3400 or remove the B&W Turnovernall Gooseneck Trailer Hitch and install the Underbed Rail...
    view full answer...
  • Recommended Sliding 5th Wheel Hitch for 2019 GMC Sierra 2500 Duramax
    I recommend using the Demco Hijacker Autoslide # DM8550037, which has a 21,000-lbs capacity and can be adjusted between 15-1/2 - 18-1/4 inches tall. This is an automatic sliding hitch, so there won't be any need to get in and out of the vehicle each time you need to perform a tight turn that might otherwise have your trailer getting a little too close for comfort to the truck cab. You will need to use the custom installation kit # DM8551010 to provide you with the mounting rails for the...
    view full answer...
  • Recommended Demco Hijacker Autoslide Compatible with 2012 GMC Sierra and 2021 GMC Sierra
    I have a solution for you, but Demco does not make a hitch that will drop directly into the pucks on a GMC truck, so you would have to use an adapter on the new truck. For the hitch, you can use the Demco Hijacker Autoslide # DM8550035; this hitch has a 21k capacity and will fit into industry standard base rails or the adapter mentioned below. I think it's always a good bet to go up to a higher capacity if there's a chance that you might end up with a trailer that's higher weight; so if...
    view full answer...
  • Are Demco Autoslide 5th Wheel Hitches For Underbed & Above Bed Rails the Same
    The Demco Hijacker Autoslide 5th wheel hitches that fit the underbed rails and above-bed rails are exactly the same but for the side plates they come with. The side plates are what attach the Hijacker to its respective rails, and apart from that there is absolutely no difference whatsoever between the two hitches. So, depending on what style you want, you can choose from one of the following options: - Underbed: Demco Hijacker Autoslide 5th Wheel Trailer Hitch with Slider # DM8550022 -...
    view full answer...
  • Best Auto Sliding 5th Wheel Hitch for a 2018 Chevrolet Silverado 2500
    The best auto sliding 5th wheel hitch for your 2018 Chevrolet Silverado 2500 is the Demco Hijacker Autoslide 5th Wheel Trailer Hitch. This hitch is rated for use up to 21,000 lbs, has an auto sliding base which provides up to 14" of front to back travel, and uses a rail free design that allows for full access to truck bed when the hitch is removed. If you have the factory rail kit then you are going to want to use part # DM8550035 for the hitch and part # DM6194 for the adapter. If you...
    view full answer...
  • Recommended 5th Wheel Hitch And Underbed Rail Kit Compatible With Revolution On 2012 GMC Sierra 2500
    There is only one underbed rail and hitch system we carry that is compatible with your 2012 GMC Sierra 2500 and a Revolution pin box. My recommendation is the Demco Hijacker UMS Double Pivot 5th Wheel Trailer Hitch - Single Jaw - Underbed - 21,000 lbs, # DM8550032 and the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches, # DM8551010. This system will give you a rail free design that will allow full access to your truck bed then hitch is...
    view full answer...
  • Best Autoslide Fifth Wheel Hitch With Underbed Rails for 2018 Chevy Silverado 2500
    For your 2018 Chevy Silverado 2500 there is a great auto-slide fifth wheel hitch available with underbed rails, the Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider # DM8550022 which you would mount with Underbed Rail and Installation Kit for Demco Hijacker UMS # DM8551010 The Hijacker is a premier hitch with an automatic slider which is a great quality-of-life feature because it means not having to hop in and out of your Chevy just to make a sharp turn. This hitch offers complete...
    view full answer...
  • Recommended Sliding 5th Wheel Hitch for a 2015 Chevrolet Silverado 2500HD Short Bed
    I have two great options for your 2015 Chevrolet Silverado 2500HD; one that is easy to use as it operates automatically, the Demco Hijacker Autoslide 5th Wheel Trailer Hitch part # DM8550022 with the Underbed Rail and Installation Kit part # DM8551010 or one that is easier to remove, the Curt A16 5th Wheel Trailer Hitch part # C16521 with the Curt Custom Fifth Wheel Installation Kit part # C16411-204. The Demco Hijacker is great because you don't have to get in and out of the truck to...
    view full answer...
  • Gooseneck Hitch Adapter Recommendation for the Demco Fifth Wheel UMS Rail Kit DM8551010
    The Demco Rail Kit part # DM8551010 that you referenced is a confirmed fit for your 2015 GMC Sierra 2500 Short Bed. The gooseneck hitch adapter you would need to go with this rail kit is the part # DM5988.
    view full answer...
  • What Does Demco Hijacker Autoslide and Rail Kit for 2019 Chevy Silverado 3500 Weigh
    The combined weight of the Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed # DM8550022 and the rail kit part # DM8551010 that fits your 2019 Chevy Silverado 3500 short bed is 374 lbs. You should note that this does not count against your payload as that is the weight capacity of the truck bed whereas this attaches to the truck frame directly for supporting the weight.
    view full answer...
  • 7-Way Trailer Wiring Connector for Bed of 2016 GMC Sierra 3500
    Sounds you are referring to 7-way wiring ran to the very rear of the truck near the bumper. So what you would need to install a 7-way in the bed of the truck is the 5th wheel 7-way wiring kit part # 50-97-410. This plugs inline to that connector and gives you a harness and 7-way that will reach up to the wheel well. I attached an install video for this kit on a 2016 GMC Sierra 3500 just like yours as well.
    view full answer...
  • What is the Best Truck for Towing a 5th Wheel Trailer
    You are doing the right thing by doing the research first. There is a lot of conflicting information out there so let me break it down for you and I will provide some part recommendations at the end. Basically, if you want to tow a 5th wheel trailer, the best trucks are going to be long bed 3/4 or 1 tons like a Ford F-250/F-350, Chevy/GMC 2500/3500, or Ram 2500/3500. Half ton trucks could work but are not nearly as capable as the larger trucks. A long bed for sure is something you will...
    view full answer...
  • Recommended Rail Kit to Move the Demco Hijacker from 2008 Ford F-350 to 2016 Chevy Silverado 2500
    The only thing that you will need to change to be able to use the Demco Hijacker 18K # DM8550022 on your 2016 Chevrolet Silverado 2500 is a new underbed rail and installation kit. Since the chassis on a 2008 Ford F-350 and a 2016 Chevrolet Silverado 2500 are different, you will need to use a different installation kit. The kit that you will need to use for your Silverado is part # DM8551010. I also recommend installing a 5th wheel and gooseneck wiring harness. Curt has a 7-Pole Harness,...
    view full answer...
  • Installation of UMS Demco 18K Auto Slide Base Rails on a 2015 GMC 2500 Sierra Diesel Crew Cab
    I took a look at the directions and they are straight forward and provide clear diagrams. According to them there may be the need to trim the heat shield on some models but they provide another excellent diagram showing exactly where to trim if this is needed for your truck. I have linked a few images for you to check out. They also recommend lifting the trucks rear end for better access to install base rails. The manufacturer does offer two methods of install based on your situation. Estimated...
    view full answer...
    Image 1 for Image 2 for Image 3 for
  • Demco 5th Wheel Hitch That Works With A 2022 Chevrolet Silverado 2500 W/ A Short Bed
    In order for the Demco UMS Double Pivot 5th Wheel Trailer Hitch to fit your 2022 Chevrolet Silverado 2500 you would need the Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches # DM8551010, however Demco does not have a kit that is available that fits your 2022 Chevrolet Silverado 2500. Instead, I recommend checking out the Demco Autoslide 5th Wheel Trailer Hitch w/ Slider # DM8550035 with the base rails # DM39FR. This hitch has the same maximum towing...
    view full answer...
  • Do Demco Fifth Wheel Rails Require Demco Fifth Wheel to Gooseneck Adapter
    Demco uses/used a few different styles of fifth wheel rails over the years so the key will be determining what rails you have now so that we can pick out the correct adapter you'd need. The part # DM5988 you referenced is for the UMS style rails which are an underbed rail that looks like part # DM8551010. If you have what looks like standard fifth wheel rails that sit on top of the truck bed and are spaced 22 inches apart like part # RP30035 then you can use more of a standard gooseneck...
    view full answer...


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Info for this part was:

Employee Joe V
Test Fit:
Joe V
Employee David F
Test Fit:
David F
Employee Lindsey S
Edited by:
Lindsey S
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Joshua S
Video Edited:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Dustin K
Video by:
Dustin K
Employee Kristina F
Written by:
Kristina F
Employee Noah M
Updated by:
Noah M
Employee Carrie F
Updated by:
Carrie F
Employee Justice A
Updated by:
Justice A
Employee Andy C
Installed by:
Andy C

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