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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: $499.39
You Save: $199.60
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)
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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:

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:

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:
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

  • Recommended Auto Sliding 5th Wheel Hitch for 2019 Chevy Silverado 2500 Short Bed
    The hitch you need will depend on whether your truck is equipped with the factory tow/prep package with the pucks sunk into the truck bed and the weight capacity you're looking for. For a truck equipped with the tow prep package, for a 18K rated hitch go with The Demco Hijacker Autoslide # DM8550034 and the # DM6194 install adapter. For a 21K capacity, use the # DM8550035 hitch along with the same # DM6194 adapter. If your truck doesn't have the pucks in the truck bed, use the # DM8550022...
    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...
  • Auto Sliding Fifth Wheel Hitch for 2017 Chevy Silverado 2500 Short Bed without OEM Rail Kit
    We don't carry the Pullrite brand of hitches but we do offer an auto sliding hitch setup that will work just as good if not better than the Pullrites which aren't height adjustable. The Demco Hijacker AutoSlide part # DM8550037 is a really great auto sliding hitch that is a little easier to install and use than the Pullrite too since it doesn't require a capture plate. It also has a 21k trailer towing capacity. This installs in an underbed rail kit for your truck with part # DM8551010...
    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...
  • 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...
  • Recommended Slider 5th Wheel Hitch With Clean Bed Once Removed for a 2016 Chevy Silverado 2500
    The best fifth wheel hitch option for a 2016 Chevrolet Silverado 2500 6.5' bed without prep package is the Demco Hijacker Autoslide 5th Wheel Trailer Hitch. The reason that this hitch is the best option is because of the auto-slide mechanism which will allow you to make tight turns without having to get in and out of the truck to adjust the hitch. It will also allow for a clean truck bed when using part # DM8550037 which is rated at 21,000 lbs with the Underbed Rail and Installation Kit...
    view full answer...
  • Parts Needed To Install Demco Autoslide 18K 5TH Wheel Hitch On 2019 GMC Sierra 2500 With UMS
    Yes, you do have the correct part numbers. For your Demco Autoslide 5th Wheel Trailer Hitch # DM8550034 the Side Plates # DM6003 are the part number 6003 you referenced. To mount on the Underbed Rail and Installation Kit # DM8551010 for your 2019 GMC Sierra 2500 you will need the Side Plates # DM6004.
    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...
  • 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...
  • 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...
  • 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...
  • 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...
  • 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 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 that...
    view full answer...
  • Will the Reese Goose Box Work on a 2015 Chevy Silverado 3500 Short Bed
    I do have an option for you but you will more than likely run into turning clearance issues when using a Reese Goose Box 5th-Wheel-to-Gooseneck Air Ride Coupler Adapter like part # RP85FR on a truck with a bed shorter than 6-1/2' long. Instead, I recommend a sliding 5th wheel hitch. For a sliding 5th wheel hitch that will work with your 2015 Chevrolet Silverado 3500 that has a 6-1/2' bed and will allow for a clean look once removed, I recommend the Reese Elite Series Pre-Assembled 5th...
    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...
  • 5th Wheel Trailer Hitch and Install Kit for a 2016 GMC Sierra 2500 Long Bed
    First you will need an installation kit to mount the 5th wheel hitch in your 2016 GMC Sierra 2500 long bed. There are kits with rails above the bed and kits below the bed. The advantage of below the bed is that the bed is clear when the hitch is removed. If you want to go with above the bed rails I recommend Reese custom installation kit # RP56001-53. There is no drilling required to install the frame brackets and the longer rails and outboard frame brackets make installation much easier...
    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...
  • 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...
  • 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...
  • 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...
  • 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...
  • 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...
  • 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...


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Info for this part was:

Employee Joe V
Test Fit:
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Employee David F
Test Fit:
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Employee Lindsey S
Edited by:
Lindsey S
Employee Michael H
Expert Research:
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