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Demco Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed - 21,000 lbs
Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches

Part Numbers: DM8550037,DM8551010

Retail:$3,371.99
Our Price: $2,754.20
You Save: $617.79
Fifth Wheel Hitch

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Demco Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed - 21,000 lbs
part number: DM8550037

This hitch slides automatically as you drive to give you 14" of additional clearance for tight turns. A wraparound jaw provides a smooth ride and a locking bar offers added security. Hitch removes easily for full bed access.

Features:

  • 5th-Wheel hitch mounts in your short-bed truck bed so you can tow your 5th-wheel trailer
  • Automatic slider provides clearance required for your short-bed pickup to turn safely at slow speeds
    • No more getting into and out of the truck to operate a manual slider
    • Head slides toward the tailgate when you turn and back toward the cab when you straighten out
    • Rack-and-pinion gears create smooth, controlled, automatic motion
  • Rotating hitch head turns up to 90 degrees with your trailer
    • Rotation creates the force that propels the automatic slider
    • Built-in brackets stabilize your pin box so the king pin won't rotate in the hitch - no need for a separate capture plate for standard pin boxes
  • Rail-free design allows for full access to truck bed when hitch is removed
  • Wraparound, single-piece jaw provides a secure connection
    • 360-Degree jaw-to-king-pin contact
    • Less rattle and more security than slide-bar jaws
  • 3/4" Thick, solid steel locking bar reinforces the connection of your coupled trailer
    • Automatically locks into place when the jaw closes
  • Double-pivot hitch head eases hookup and helps to limit chucking
    • Pivots front to back and side to side
  • 3 Height settings to fit your application
  • Cushioning polyurethane dampeners help reduce noise and absorb road shock
  • Spring-loaded handle with comfort grip allows for simple coupling
    • Tethered safety pin lets you secure the handle in the open or the closed position
  • Sturdy steel construction with rust-resistant black powder coat finish
    • Diamond-plate tread on hitch base adds unique styling
  • Custom Demco underbed mounting kit required for installation
  • Made in the USA


Specs:

  • Designed for use on 6-1/2' truck beds
  • Fits standard pin boxes 12" - 14" wide
    • Locking plates (sold separately) are required for use with Glide Ride, Mor Ryde, Trailair Tri Glide, Trailair Flexair, Rota Flex, and 5th Airborne pin boxes
  • Gross towing weight: 21,000 lbs
  • Vertical load limit: 5,250 lbs
  • Travel: 14" front to back
  • Hitch height settings: 15-1/2", 16-3/4", and 18-1/4"
  • 5-Year limited warranty


Note: This fifth-wheel trailer hitch is not compatible with Sidewinder or Revolution king pins. Do not use any device that changes the pivot point of your trailer's king pin with this hitch.


Automatic Slider Makes Cornering Easy

Most often used on trucks with 6-1/2' beds, a slider helps to eliminate clearance problems during slow-speed turns. When you are towing a fifth-wheel trailer, your hitch must be situated on the cab side of your truck's rear axle. However, at slow speeds you can use a slider to slide the fifth-wheel hitch (and the trailer) toward your truck's tailgate and past the rear axle, creating enough space between the cab of your truck and the trailer to permit less-restricted turning.


Normally, you'd have to get out of your truck and pull a lever to release the slider before every turn, but what if there was an automatic system? Imagine having 14" of extra clearance while towing your fifth-wheel trailer. Now imagine having this without needing get out of the truck to move your slider. The Demco Autoslide makes this fantasy a reality. The Autoslide automatically glides back smoothly when you make a sharp turn so you can maneuver effortlessly around tight corners within campsites and parking lots.


Demco Hijacker Autoslide

The base of the Autoslide has a built-in rack-and-pinion gear system that operates automatically. As your truck turns, the pinion in the base also turns. This activates the rack gear, which causes the rotational force of the truck to be converted into the linear sliding action of the hitch. So, when your truck makes a sharp, slow-speed turn, the gears inside the Autoslide force the hitch head to slide down toward your truck's tailgate in a smooth, controlled motion. This way, any time that your truck turns more than 10 to 15 degrees, the Autoslide will ensure that there is enough clearance for your trailer to complete the turn as well, and it will do so without any jerking or binding.


In order for the rack-and-pinion assembly to function as designed, the pin box must be stabilized on the hitch head. Normally in a fifth-wheel hitch, the king pin moves inside of the hitch head so that the trailer can turn. With the Autoslide, the king pin remains fixed inside of the jaws of the hitch and it is the hitch head itself that turns. This is thanks to the capture brackets on the sides of the head that brace the pin box from both sides to hold it in place on top of the hitch head. This is done to ensure that there is enough resistance within the hitch when your truck turns to properly activate the rack-and-pinion gear mechanism.


Demco Hijacker Autoslide capture bracket

To stabilize your pin box on the hitch head, simply push the capture brackets up against your pin box once the trailer is coupled and tighten the outer bolts and the inner jam nuts. The Autoslide head and brackets will fit standard pin boxes that are between 12" and 14" wide. If you have a Glide Ride, Mor Ryde, Trailair Tri Glide, or 5th Airborne pin box, you must install a special locking plate (sold separately) as well.


When you straighten your rig out again and your trailer moves back in line, the hitch head will rotate back to center and slide back toward the cab into the straight towing position.


Secure Wraparound Jaw with Locking Bar

Demco Hijacker Autoslide wraparound jaw and locking bar

The single-piece, strong wraparound jaw completely surrounds your trailer's king pin for 360 degrees of contact. This wraparound jaw provides a more secure connection than standard 2-piece jaws that close in on the king pin from the sides. The increased jaw-to-king-pin contact on the Autoslide offers tighter tolerances around the king pin, which minimizes both rattle and chucking, for a smooth, quiet ride.


A 3/4" solid steel locking bar spans the area in front of the jaw. This bar provides an added barrier of protection against accidental disconnection so you can have peace of mind that your trailer is secure. The locking bar is attached to the jaw and to the spring-loaded handle. The bar automatically locks when the jaw closes around your king pin.


Double-Pivot, Cushioned Hitch Head

The double pivoting, cushioned head improves your towing experience dramatically by helping to reduce jarring and unwanted noise. Built-in pins allow the hitch head to pivot back and forth and side to side. And hooking up is easy because the hitch head will automatically pivot to the proper angle when it comes into contact with your pin box.


Three polyurethane dampeners help to cushion the movement from the pivoting head and to reduce towing noise. Two of these dampeners are built into the head assembly to cushion the head's side-to-side pivoting. The third dampener cushions the back-and-forth motion and must be installed in the hitch prior to use. Installation of this third dampener is easy - simply press the dampener up into the pre-drilled hole underneath the hitch head.


Easy Installation

The Autoslide hitch is specially designed to fit a Demco UMS custom underbed mounting kit . The hitch comes pre-assembled for an easy installation. All you have to do is bolt on the side plates and attach the head to the hitch base.


The side plates have 2 functions. They contain the feet that fit into the receivers in your truck bed, and they allow you to raise or lower the hitch head to better match your pin box height. After you choose your desired height setting, simply bolt the side plates to the hitch base with the included hardware. Then lower the hitch into the 4 UMS receivers in your truck bed. Turn the handles to lock the feet into the receivers and secure the handles with the included safety pins. The hitch can be removed to give you full truck bed access. Simply remove the safety pins, turn the handles to unlock the feet, and lift the hitch out of the receivers.


Clearance Formula for Short Bed Trucks

Use the formula below to ensure there will be enough space between your truck cab and trailer when executing a 90-degree turn.


(A+B) - C = Clearance


A = Distance from the center of fifth-wheel hitch jaw to truck cab

B = Length of Travel (14")

C = Width of trailer divided by 2 (to get half)


For example: If the distance from the center of the hitch to the cab is 36", 36" + 22" = 58". If your fifth-wheel trailer is 102" wide, take half (51"), then plug in: 58" - 51" = 7" of clearance.


Note: At least 4 inches of clearance is recommended to safely execute a 90-degree turn.



6107 Demco Hijacker Head Assembly for Auto Slide 5th Wheel Trailer Hitch - 21,000 lbs

6004 Demco Hijacker Adapter Plates for Underbox Mount 5th Wheel Trailer Hitch



Underbed Rail and Installation Kit for Demco UMS 5th Wheel and Gooseneck Trailer Hitches
part number: DM8551010

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




Customer Satisfaction Score:


Customer Reviews

Demco Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Underbed - 21,000 lbs - DM8550037

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

Average Customer Rating:  4.7 out of 5 stars   (610 Customer Reviews)

This hitch slides automatically as you drive to give you 14" of additional clearance for tight turns. A wraparound jaw provides a smooth ride and a locking bar offers added security. Hitch removes easily for full bed access. 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: John 06/13/2024

After a year, I still like my Demco autoslide. It works great. I have pulled my trailer quite a few times and have had no issues at all. I know quite a few people that pull 5th wheels and one actually went out and purchased a autoslide after watching mine work.



by: Richard H. 05/13/2016

This hitch has been used daily since i purchased it. I deliver fifth wheel travel trailers all over the country. This hitch has worked flawlessly from day one. This hitch is one of the only products that I've ever bought that is exactly what it was described to be. Im not one to do reviews, so the fact that im doing this one , in itself, says a lot about the quality of your product. The design and looks are much better than any other hitch ive seen. It just looks better in the truck bed than others do.



by: Brian05/28/2020

Instructions left alittle to interpretation when it came to hitch height in the bed of the truck. For a f350 super duty it is the medium set up. Save you some time and effort. Other then that it looks great and will be testing it out this weekend.



by: Charles12/26/2018

Great hitch for a short bed truck thanks etrailer



by: Jason11/09/2018

Hitch works great. Had some issues using it when I first got it with putting the pin to lock down the handle but its worked much better lately. The hitch is heavy so I leave it in the back of the truck. Wish I could remove it so it doesn't get weathered.



by: Devin05/09/2020

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.



by: Dave 10/01/2019

great hitch for my customers new truck to pull his new Durango 5th wheel!

Fast Delivery as well

Always RV
Mesa Az



by: Gary08/15/2021

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: Michael 10/21/2016

Hitch sucks pain in the assembly to connect and disconnect.



by: David S.01/03/2020

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: Kyle04/07/2019

Great functional hitch. Poor powdercoating though (mostly flaking off) with quite a bit of rust after only a year.



by: Myron09/17/2018

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: Kirk C.07/25/2019

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: Mike06/26/2018
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: Jeffrey10/15/2018
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: Wayne 10/01/2022



by: Donald05/09/2019

It arrived in two days. Great delivery.



by: Dennis03/19/2022



by: Jeff 03/08/2023



by: Todd10/31/2022



by: Michael 09/03/2021



by: Gary 09/01/2022



by: Todd 08/13/2021



by: James 08/12/2021



by: Eric10/04/2022


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Ask the Experts about this Fifth Wheel Hitch
Do you have a question about this Fifth Wheel Hitch?


  • Which 21k Demco Hijacker Fits OEM Pucks of 2020 Ford F-350
  • The Demco Hijacker part # DM8550037 that you referenced was designed to fit Demco's under bed mount system and not the Ford pucks you have in your 2020 Ford F-350. The version that fits your truck pucks is the # DM8550038. If you have the UMS version you could swap the side plates to the part # DM6033 and it would then fit your truck.
    view full answer...

  • Should I Choose Demco, Reese, or PullRite Underbed Rail System for My 2020 Chevy Silverado 2500
  • For your application I recommend installing the Demco UMS Underbed Rail Kit # DR37FR on your 2020 Chevy Silverado 2500 and using the Hijacker Autoslide # DM8550037. The reason behind this is twofold; the Hijacker has more height adjustability and it comes with capture plates (as opposed to sold separately), and then Reese doesn't have an underbed rail system for your truck so you'll have to use the matching underbed rails for the 5th wheel hitch. Since the Demco Hijacker is better than
    view full answer...

  • Compatibility of a Demco Hijacker 21K Under Bed Rails With a B&W Under Bed Gooseneck Hitch
  • If you are installing the Demco Under Bed Rails, # DM8551005, for the 2011 Ram 2500 truck, then the B&W Under Bed Gooseneck Hitch, like # BWGNRK1313, will have to be remove to allow for the installation for the Demco Hijacker 5th Wheel hitch. The gooseneck hitch will interfere with the 5th wheel rails installation. The gooseneck mounting braces might cover the frame area where the 5th wheel brackets will need to be installed. Removal of the gooseneck hitch is necessary.
    view full answer...

  • Below Bed Base Rails for 2002 Ford F-250 and Demco Hijacker Autoslide 5th Wheel Trailer Hitch
  • You can absolutely use the 18,000 lb Demco Hijacker Autoslide with the underbed rails on your 2002 Ford F-250 crew cab. What you need are the following: - Underbed Rail and Installation Kit for Demco Hijacker # DM8551000 - Demco Hijacker Autoslide 5th Wheel Trailer Hitch with Slider - 18,000 lbs # DM8550022 As you mentioned, this is also compatible with the 21,000 lb version of the Hijacker # DM8550037. Additionally, if your '02 F-250 has the factory 7-way but you need a 5th wheel
    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
    view full answer...

  • Determining Pin Weight Of a 5TH Wheel Trailer When Adding Additional Cargo
  • The only way adding 1718lbs of cargo to your 5th wheel would increase the hitch weight the same amount would be if you place all the weight directly over the hitch. Since this really isn't feasible you will not see your hitch weight increase that amount. To give yourself a rough estimate if your cargo weight is loaded half way between the hitch point and the axles then 50% of the weight is a rough calculation on the additional hitch weight. Do remember to add the weight of your 5TH
    view full answer...

  • Underbed Auto Sliding Hitch for 2013 Ram 2500 Short Bed
  • For an under-bed autosliding fifth wheel hitch solution for your 2013 Ram 2500 the best option is the Demco Hijacker Auto Slider part # DM8550022 and the underbed rail kit part # DM8551005 and you'd be set. Or if you need a higher 21k capacity hitch you'd want the part # DM8550037 instead. If your truck has a standard suspension height you'd have nothing to worry about. If you have a suspension lift beyond that it would really depend on how big of a lift the truck has.
    view full answer...

  • Choosing Between the Demco Autoslide and B&W Companion for 2020 Ford F-250 without OEM Prep Package
  • I can understand why a hitch like the Demco Hijacker Autoslide # DM8550022 (18k) or # DM8550037 (21k) is so attractive; they provide a much better solution for towing a 5th wheel with a short bed truck when it comes to not having to get in and out of the truck each time you need to make a tight turn. With that said, they're not compatible with B&W Turnoverball Underbed kits like the # BWGNRK1116-5W since the hitches connect to the underbed kit in two very different ways. In order to
    view full answer...

  • Can Demco Hijacker Autoslide 18K Be Converted To 21K?
  • The only difference between the Demco Hijacker Autoslide 18k # DM8550024 and the 21k # DM8550037 is the base assembly. Both use the same head, but the base is what gives each hitch its rating. To change the 18k to 21k you would need the 21k base and head assembly # DM6107 and the reuse the side brackets for mounting to your 5th wheel rails. The base is not available by itself.
    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
    view full answer...

  • Recommended Autoslide Hitch for 2010 Ram 2500 Mega Cab
  • Though an auto-slide hitch is not going to give you more front-to-back travel, it is extremely beneficial because of how simple it is to use and I highly recommend the auto-sliding Demco Hijacker # DM8550037 for your 2010 Ram 2500 Mega Cab. You can mount this hitch with the Underbed Rail and Installation Kit # DM8551005, which is a confirmed fit for your truck and has underbed rails so you can remove the hitch at any time and still have full access to your truck's bed. The Hijacker uas
    view full answer...

  • Weight of 21K Demco Hijacker Autoslide 5th Wheel Hitch DM8550037
  • The 21K-rated Demco Hijacker Autoslide 5th Wheel Trailer Hitch # DM8550037 has a shipping weight of 332-lbs. The lower-rated 18K model # DM8550024 has a shipping weight of 304-lbs.
    view full answer...

  • How to Install Demco Hijacker AutoSlide Fifth Wheel Hitch in Bed of 2016 Ram 3500 with OEM Rail Kit
  • The Demco Hijacker Autoslide part # DM8550037 can easily fit in the bed of your 2016 Ram 3500 with the factory rail kit but you will have to use an adapter to provide the style of rails this hitch requires. For that you will need the part # DM6099 and you will be set! I attached a picture of what this will look like in the bed of your hitch as well as a review video for the rail kit.
    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.
    view full answer...

  • Is Head of Demco Hijacker Hitch Easy to Remove for Lightening Up Hitch Removal
  • The head of the Hijacker hitches by Demco like part # DM8550037 are pretty easy to remove. When the Demco rep came here to show us these hitches we went out and watched him install and remove the head of a Hijacker to allow the hitch to easily get removed from the rails. The head weighs right at 65 lbs which will make removing the setup much more manageable.
    view full answer...

  • Is a Sliding 5th Wheel Hitch Needed for a 2017 GMC Sierra 3500
  • The only way to be certain whether or not you have the correct fifth wheel hitch in regards to sliding vs fixed is to first measure both the truck and trailer. I understand this may be difficult if you do not physically have the trailer but is needed to ensure accuracy. There are certain truck/trailer combos that can use a fixed fifth wheel hitch and short bed and there are certain truck/trailer combos that can't use a fixed fifth wheel hitch and short bed. The general rule we use is to
    view full answer...

  • Replacement Parts Breakdown for Demco Hijacker Autoslide Hitch DM8550034
  • Thank you for purchasing the Demco Hijacker Autoslide 5th Wheel Trailer Hitch # DM8550034 back in 2017. All replacement parts we sell appear on the page I linked for you. I also linked the install instructions for this hitch and on pages 9 through 11 you'll find the complete parts breakdown with individual part numbers. Since your hitch came with a 5-year warranty you may be able to obtain some replacement parts from Demco under warranty, if you wish. Some smaller parts we may not
    view full answer...

  • Using A Lippert Turning Point Pin Box With A Demco Autoslide 5th Wheel Hitch
  • The reason the Demco Capture Plates # DM6171 aren't working with your Lippert Turning Point pin box is because they were specifically designed for Trailair Rota-Flex pin boxes. Since you have a Demco Autoslide # DM8550037 you'll need to lockout your Turning Point pin box and allow rotation only at the hitch to king pin connection point. To do this you'll need to install two 5/8" - 11 x 2" in the lockout holes in the back of the pin box.
    view full answer...

  • Sliding 5th Wheel Trailer Hitch and Under-Bed Install Kit for a 2016 Chevy Silverado 2500 Short Bed
  • We do have under-bed installation kits that will fit your 2016 Chevy Silverado 2500 short bed and hitches to match! For an under-bed install kit I recommend B&W kit # BWGNRK1016-5W. This kit also doubles as a gooseneck hitch should the need arise. For a hitch I recommend the B&W Companion hitch # BWRVK3400-5W. With this set up, when the hitch is removed, the bed will be clear. I have linked a video review of this hitch for you. I also recommend adding an in-bed 7-Way trailer connector,
    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...

  • 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...

  • 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...

  • 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...

  • 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...

  • 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...

  • 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...

  • 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...

  • 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...

  • 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...

  • 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.
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  • 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.
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  • 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
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  • 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
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  • 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.
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  • 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.
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  • 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
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Info for these parts were:

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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