Can Demco Autoslider be Used with2015 GMC Sierra 3500 Factory Gooseneck Hitch

Updated 04/19/2025 | Published 04/16/2025

Products Featured in This Question

Demco Autoslide 5th Wheel Trailer Hitch w/ Slider - Single Jaw - Above Bed - 18,000 lbs

(711)

$1795.00

Curt Custom Fifth Wheel Installation Kit for Chevy/GMC - Carbide Finish

(350)

$267.39

Question:

2015 3500hd looking to use this adapter for a DECMO auto slider hitch DM8550034, dont really want to drill holes in box to get rails mounted, would rather use the factory installed gooseneck. Does not have the puck system installed If not what do I all need would like a auto slider hitch , because I have a 6.5 box

asked by: Nathan M

Expert Reply:

Hey Nathan, thanks for reaching out!

There is a bit to unpack here, but to start things off, I'm not seeing that a 2015 GMC Sierra 3500 would have had an OEM gooseneck receiver without the rest of the pucks, so I believe you have an aftermarket system.

A single point attachment can't be used with an auto-sliding hitch like the Demco # DM8550034 because that feature will put too much torque on the single point and cause issues. The only way to use the Demco is if you install standard base rails like the Curt Custom Rail Kit # C16411-204.

With that being said, we've heard that the GM trucks don't have to HAVE to have a sliding 5th wheel hitch, as long as the nose of the 5th wheel camper is tapered. We have a clearance formula (see below) that can be used to determine if and how much clearance is required for turning. You can use it to verify whether you need a sliding hitch or not, and if you can get away with a stationary hitch, just let me know what the brand and model is for your gooseneck hitch and I'd be happy to see what kind of adapter we need to get you up and towing!

Clearance Formula:
(A + B) - C = Clearance

A = Distance from center of fifth wheel hitch jaw to truck cab
B = Length of offset (slider clearance or Sidewinder offset)
C = Width of trailer divided by 2 (to get half)

You need at least 4" of clearance to be able to make a 90 degree turn.

expert reply by: Jon G

Nathan M.

4/18/2025

They would like the auto slide hitch, right now it's a B&W gooseneck, could they install the RP30158-68 the gooseneck puck system and DM8550034? does not really want rails in his truck

Jon G.

4/19/2025

@NathanM Yes, the Reese Elite Series # RP30158-68 is a great alternative to get the puck style in the truck. The Demco part you mentioned is for above-rail setups and will require an adapter to fit with the Elite kit. Instead, I recommend going with the Demco Hijacker # DM8550024, which is the same hitch, but it comes with the base for a Ford pickup puck system. The Elite Series and OEM Ford puck systems have the same puck footprint which is why this Demco setup will work.