ram1500 5.7hemi

I have a 2013 4x4 Ram w/hemi, 6' bed, extended cab. I pull a #5000 trailer 26' with no problem, however, compared to my Chevy the rear end feels "mushy" to me and I have trailer sway from time to time, something I never had with the Chevy. I have a reese weight distribution system and reese anti sway bar,same set up I had on the Chevy. Any of you other fellas who own a Dodge notice this? I set everything up by the book when I swapped over to the Dodge. I love the truck and it comfortable and has a heap of power but I am a little disappointed in the way it tows, I had more confidence with my Chevy which had 0 sway.I asked my dealer and they told me it was because of the coil springs? Any aftermarket add ons to stiffen up the rear end?
Thanks.