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Demco Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Above Bed - 21,000 lbs
Demco Premier Series Above-Bed Base Rails and Custom Installation Kit for 5th Wheel Hitches

Part Numbers: DM8550035,DM39FR

$2,472.54
5th Wheel Hitch

In Stock
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Demco Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Above Bed - 21,000 lbs
part number: DM8550035

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. Pivoting head allows easy hook up and helps to limit chucking.

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
  • 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
  • Simple installation with base rails and installation kit
    • Compatible with B&W, Curt, Demco, Draw-Tite, Hidden Hitch, Husky, Reese, and Valley above-bed base rails
    • Cannot be used with rails that are a part of a gooseneck adapter plate - base rails must be securely bolted to your truck
  • 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, Lippert Road Armor, 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: 15-1/4", 16-1/2", and 18"
  • 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, Rota Flex, Lippert Road Armor, 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 designed to attach to universal above-bed base rails . The hitch will fit most industry-standard rails, including those from B&W, Curt, Demco, Draw-Tite, Hidden Hitch, Husky, Reese, and Valley. 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 your above-bed rails, 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 attach the base to the rails with the included safety pins.


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" + 14" = 50". If your fifth-wheel trailer is 84" wide, take half (42"), then plug in: 50" - 42" = 8" 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

6003 Demco Hijacker Adapter Plates for Auto Slide 5th Wheel Trailer Hitch

California residents: click here



Demco Premier Series Above-Bed Base Rails and Custom Installation Kit for 5th Wheel Hitches
part number: DM39FR

Install your fifth-wheel trailer hitch in your truck bed with this kit. Custom brackets reduce the amount of time required to install the hitch. Brackets, base rails, and hardware included.

Features:

  • Installation kit lets you mount your Demco Premier Series 5th-wheel trailer hitch in the bed of your truck
    • Also compatible with B&W, Curt, Draw-Tite, Hidden Hitch, Husky, Reese, and Valley above-bed 5th-wheel trailer hitches
  • Mounting brackets install beneath truck bed to provide attachment points for above-bed base rails
  • Base rails provide necessary mounting points for 5th-wheel hitch
  • Custom-fit brackets mount to your vehicle's frame
    • Drilling is required
    • Drastically reduces installation time
    • Avoids known obstacles along your truck's frame
  • Sturdy, black powder coated steel resists corrosion
  • 2 Base rails, brackets and hardware included
  • Made in the USA
  • 5-Year limited warranty


8552037 Demco Custom Bracket Kit for Hijacker Premier Series Fifth Wheel Trailer Hitches

6071 Universal Above-Bed Base Rails for Demco Premier Series Fifth Wheel Trailer Hitches

California residents: click here




Customer Satisfaction Score:

Ratings & Reviews

4.7

671 reviews
5 Stars
(1082)
4 Stars
(178)
3 Stars
(38)
2 Stars
(18)
1 Star
(26)
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. Pivoting head allows easy hook up and helps to limit chucking. Install your fifth-wheel trailer hitch in your truck bed with this kit. Custom brackets reduce the amount of time required to install the hitch. Brackets, base rails, and hardware included.

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Ask the Experts about this 5th Wheel Hitch


Info for these parts were:

Employee Jameson C
Expert Research:
Jameson C
Employee Dustin K
Video Edited:
Dustin K
Employee John S
Video Edited:
John S
Employee Wilson B
Updated by:
Wilson B
Employee Justice A
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Employee Kristina F
Written by:
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Employee Bradley B
Test Fit:
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