For nearly the same size TT I insisted they install the Equalizer 4 1200. For my heaviest trip of the season my Ram 2500 numbers (w/WD engaged) were:
Steer Axle 3300 (lighter gas engine...)
Drive Axle 4580
Trailer Axle 7340 (exactly same as yours!)
The dealer included the WDH and installation in the sale price. On the way home from the dealer, totally empty, I felt a lot of porpoising. However, once we loaded our gear & increased the tongue weight, the ride has been totally stable even in high winds, emergency stops, etc.
My EQ4 setup looks like this except my ball mount has one extra hole at the bottom (pic nabbed from the Internet...):