I have a 2019 express 2500 that has a plug under the rear bumper, the dealer says it is a new change for the trailer wiring harness. The problem is I can't find a plug to fit it and then feed a 4 way or 7 way plug. Do they exist ? No one seems to have an after market either.

 

If it is for the trailer wiring, their parts department should be able to get it. But there's a fair chance the dealer doesn't know what he's talking about.

 

My 2019 3500 passenger van came with a Hopkins 7/4 pin combo adapter. It may be the same on the 2500's. Here it is on Amazon:

 

That adapter looks good but I need the wire that plugs into the plug and then into the adapter

 

 

Thas the type I used...
So i am taking it that your vehicle doesnt have the wiring
Running to the back ?
I guess I dont follow....

 

My wires were bare... but they were there..

 

I think thats the one I have from the Factory.

It's called a Hopkins ? Or their design? It's been so long. I like what I have, but I remember it gave some puzzlement at first.