I was having an issue where my 2015 2500 was not stopping the gooseneck equipment trailer I had bought even though it stopped the 6000 lb rv fine.
After tinkering with the uconnect 5.0 I found a brake adjustment feature through the uconnect. When I started looking more I realized there is a light electric and heavy electric setting. While the light electric would not stop the gooseneck with tractor even at the highest setting, the heavy electric stopped it easily on 4.0. It also lets me save the settings for up to 4 trailers.
If you have the uconnect,check it out. It may solve your issue.
Michael