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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 # DM8551010
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Fifth Wheel Installation Kit

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Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches Below the Bed DM8551010
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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 800-298-1624 to order Demco fifth wheel installation kit part number DM8551010 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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  • Reviews (11)
  • Q & A (55)
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2017 Chevrolet Silverado 3500 - Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches

  • Below the Bed
  • Demco
  • 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


8551010 Demco High Jacker UMS Under Bed Rail Frame Bracket Kit

Replaces Demco DM8551002 and DM8551003

Installation Details DM8551010 Installation instructions


Customer Reviews

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

Average Customer Rating:  4.1 out of 5 stars   (11 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.

- DM8551010
by:

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


Comments
That is because this product only fits vehicles without The OEM Prep Package. You want something like this: Item # DM6194.
-- Etrailer Expert Sierra K - 08/23/2021


- DM8551010
by:

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


Comments
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.
Kirk C - 07/26/2020


- DM8551010
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.



- DM8551010
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.



- DM8551010
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.



- DM8551010
by:
2012 Chevrolet Silverado



- DM8551010
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



- DM8551010
by:



- DM8551010
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- DM8551010
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- DM8551010
by:

It arrived in two days. Great delivery.


11
11

Ask the Experts about this Demco Fifth Wheel Installation Kit

  • Gooseneck Adapter that Fits Demco UMS Underbed Rail Kit of GMC Sierra
    For the UMS underbed fifth wheel rail kit you have installed in your 2015 GMC Sierra 2500 all you'd need is the part # DM5988 and you'd be set.
    view full answer...
  • Installing Demco 5th Wheel Underbed Rails Compatible with Demco 8550022 Fifth Wheel Hitch
    For your Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed - 18,000 lbs # DM8550022 the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches # DM8551010 will work well. I've attached the installation details to help you determine the mounting to your frame which will then give you the correct bed locations. I've attached a drawing from the installation instructions as well as the complete instructions to assist.
    view full answer...
    Image 1 for
  • Install Instructions for Demco Fifth Wheel Rail Kit # DM8551002
    If you check out the video I attached below you'll see an install we did for the Demco rail kit part # DM8551010 on a 2016 Chevy Silverado 2500HD just like yours. This will walk you through the entire process and will be more helpful than the written instructions.
    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...
  • 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
  • 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...
  • Do 16k and 20k Fifth Wheel Hitches Connect to Same Size King Pin
    All of the fifth wheel hitches we carry are designed to fit the same size king pin on a trailer. A 16k hitch would work just as well to connect to a fifth wheel trailer as a 20k fifth wheel hitch. I attached a link to a page that has all of the 20k fifth wheel hitches we offer.
    view full answer...
  • Underbed Demco Hijacker Hitch and Rail Kit Recommendation for 2016 GMC Sierra 3500
    There is a great underbed rail system that Demco offers for their Demco Hijacker Autoslide hitches. The rail system you'd need for your 2016 GMC Sierra without the factory rail kit is the part # DM8551010. Then for a hitch you'd need the part # DM8550022 for the 18k version or the part # DM8550037. The Trailair pin boxes can be used with the Demco Hijacker but not the RotaFlex. To use one with a Mor/Ryde pin box requires the locking plate part # DM6025.
    view full answer...
  • Are there Covers for the Holes in Underbed Rail and Installation Kit # DM8551010
    There are no covers for the holes for the Underbed Rail and Installation Kit # DM8551010. That means that it is possible for debris to get in the holes. If that happens and it affects the fit of the hitch then I recommend using compressed air to clear out the debris.
    view full answer...
  • Recommended Under Bed Rails and Fifth Wheel Hitch for 2016 GMC Sierra 2500HD
    While there are fifth wheel hitches that will work with underbed rails on your 2016 GMC Sierra 2500HD, the Curt Q24 # C16245 hitch you referenced only fits above-bed rails. For a fifth wheel hitch I recommend checking out the Demco Hijacker UMS Double Pivot 5th Wheel Trailer Hitch # DM8550032 because of its highly secure jaw system and cushioned dampeners which are going to make your ride much more pleasant than driving with a hitch that does not have cushioning. The Hijacker uses...
    view full answer...
    Image 1 for
  • Parts Needed To Use Demco Hijacker With OEM Prep Package On 2021 Chevrolet Silverado 2500 HD
    Congratulations on the new truck! To change your Demco Hijacker Autoslide # DM8550022 that was made for the Underbed Rail and Installation Kit # DM8551010 on your 2017 GMC Sierra 2500 HD to work with your new 2021 Chevrolet Silverado 2500 HD W/ OEM Prep Package you will need to change the side plates and use a rail adapter. The correct parts are Replacement Side Plates for Demco Hijacker Autoslide 5th Wheel Trailer Hitches # DM6003 and Demco 5th Wheel Rail Adapter for Chevy/GMC...
    view full answer...
  • 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...
    view full answer...
  • 5th Wheel Hitch Recommendation For 2017 Chevy Silverado Short Bed
    You will want to install a below bed rail style of fifth wheel rail kit in your 2017 Chevy Silverado 2500 short bed since you want truck bed access when not towing. I really like the Demco Hijacker setup that uses the under bed rails part # DM8551002 which are custom fit for your truck. Then since you need a slider hitch to make tight turns you would want the Demco Hijacker Autoslide part # DM8550022 which will slide as you make tight turns.
    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...
  • 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. Tow Ready has a 7-Pole...
    view full answer...
  • 18k Slider Hitch Recommendation for 2020 Ram 3500 with OEM Rail Kit
    If you are going to be over the towing capacity of your fifth wheel hitch it would time to replace it with a higher rated one. You may have gotten away with it in the past and can't see any obvious signs of fatigue or stress but that doesn't mean you'd always be able to get away with. Since you need a slider hitch due to having a short bed truck one really great solution is an automatic sliding hitch like the Demco Hijacker part # DM8550034. As you go to make tight turns this will slide...
    view full answer...
  • Are There Replacement Brackets For DM8551010
    The brackets and hardware are not available as separate purchases, so you would need to get the full kit, which is the Underbed Rail and Installation Kit for Demco Hijacker UMS 5th Wheel and Gooseneck Trailer Hitches # DM8551010. I have added a link below to a video install for you to check out as well if you'd like to take a look.
    view full answer...
  • Parts Needed To Install Demco Hijacker Autoslide With Underbed Rails On 2017 Silverado 2500 Diesel
    I definitely understand how the above bed rails can get in the way when your Demco Hijacker Autoslide 5th Wheel Trailer Hitch w/ Slider # DM8550034 is removed. There is a way to convert your Hijacker # DM8550034 to underbed rails but you will need to install the Underbed Rail and Installation Kit for Demco Hijacker # DM8551010 and remove your current above bed rail system. You can then use Replacement Side Plates for Demco Hijacker Autoslide 5th Wheel Trailer Hitches # DM6004 to allow...
    view full answer...
  • Recommended Fifth Wheel Hitch Setup for 2017 GMC Sierra 3500 to Tow 2020 Keystone Fuzion
    The Curt Q20 5th Wheel Hitch # C16671 that you referenced is a great option to tow your 2020 Keystone Fuzion if you decide to have your GM dealership install their factory below bed rails. We have some great aftermarket options for you that you can get from us here at etrailer.com. Aftermarket systems are typically less expensive than factory options without sacrificing safety, capacity, or features. For a complete underbed rail 5th wheel system for your 2017 GMC Sierra 3500 Denali,...
    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...
  • How to Install the Demco 18K Hijacker Autoslide 5th Wheel Trailer Hitch on a 2011 GMC Sierra 2500
    In order to mount the Demco 18K Hijacker Autoslide 5th Wheel Trailer Hitch part # DM8550022 in the bed of your 2011 GMC Sierra 2500 you will need to use the Underbed Rail and Installation Kit for Demco Hijacker Hitches part # DM8551010. The Replacement Side Plates for Demco Hijacker Autoslide 5th Wheel Trailer Hitches part # DM6004 that you referenced is designed to allow the above bed version of the Demco 18K Hijacker Autoslide 5th Wheel Trailer Hitch part # DM8550034 to be used with...
    view full answer...
  • How to Tell if 2016 Chevy Silverado 2500 Has Factory Rail Kit for Fifth Wheel Hitch
    Most likely you would know if you had the Factory Rail Kit in your 2016 Chevy Silverado 2500. There would be holes in the bed of your truck that the feet of a fifth wheel hitch would fit into. I attached a picture that shows what they pucks/holes would look like. If you have them the B and W Hitch part # BWRVK3700 that you referenced would fit and work well. Otherwise for an underbed fifth wheel hitch setup I would recommend the Demco Hijacker part # DM8550022 which will automatically...
    view full answer...
    Image 1 for
  • Is Demco Hijacker Autoslide Hitch Solid Hitch for 2015 Chevy Silverado 2500HD Short Bed
    The Demco Hijacker Autoslide part # DM8550034 is a really great, solid hitch that makes towing a fifth wheel trailer with a short bed truck much easier since you don't have to get out and operate the slider mechanism. To install it in your 2015 Chevy Silverado 2500 short bed would only require you to install the Demco rail kit part # DM8551010 and you'd be set.
    view full answer...
  • Will the Demco Hijacker Work with a MOR/ryde Pin Box
    Yes, the Demco Hijacker Autoslide 5th Wheel Trailer Hitch part # DM8550022 with the Underbed Rail and Installation Kit part # DM8551010 will fit your 2015 Chevrolet Silverado 2500 with the 6-1/2' bed and work with the MOR/ryde pin box you have on your 2018 Jayco Eagle 5th Wheel Trailer. However, in order to prevent the kingpin from rotating inside the hitch you will need to use a locking plate like part # DM6025.
    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...
  • Best Fifth Wheel Hitch Recommendation for a 2015 GMC Sierra 2500 Short Bed
    Since you have a short bed truck you are going to need to get a slider fifth wheel hitch to allow you to make tight turns. Since getting out and operating the slider every time you get to a parking lot can be a bit of a hassle I would recommend the Demco Hijacker AutoSlide part # DM8550022. This hitch will automatically slide back when making tight turns. If you are looking for the best setup this would be it. The rail kit you would want would be the underbed kit part # DM8551010...
    view full answer...
  • Demco Hijacker Autoslide Underbed Fifth Wheel Trailer Hitch on 2016 GMC Sierra 2500
    For your 2016 GMC Sierra 2500 with a 6-1/2 foot bed the Demco Hijacker Autoslide # DM8550022 is the underbed fifth wheel hitch you'll want. It installs with the Custom Underbed Rail and Installation Kit # DM8551010. The Hijacker is an autoslide that will travel up to 14 inches. With many sliding hitches you need to get out of your truck to adjust the slider, make your turn, and then adjust it back to continue towing. With the Hijacker it will automatically slide when you're making...
    view full answer...
  • Can the Demco Hijacker 8550034 be Used with an Under Bed Mount Kit on a 2019 Chevy Silverado 3500
    Absolutely, the Demco Hijacker Autoslide 5th Wheel Trailer Hitch part # DM8550034 is for above bed mounting rails. However, you can make it compatible with the underbed mounting kit for your 2019 Chevrolet Silverado 3500 which is the Underbed Rail and Installation Kit for Demco Hijacker part # DM8551010 by obtaining the Replacement Side Plates for Demco Hijacker Autoslide 5th Wheel Trailer Hitches part # DM6004. I also recommend that you purchase an in-bed 7-way like the Demco 5th Wheel/Gooseneck...
    view full answer...

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Info for this part was:

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Test Fit:
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Employee David F
Test Fit:
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Employee Lindsey S
Edited by:
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Employee Michael H
Expert Research:
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Employee Jameson C
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Employee Joshua S
Video Edited:
Joshua S
Employee Jacob T
Video Edited:
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Employee Dustin K
Video by:
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Employee Kristina F
Written by:
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