2011 Ram dually: best susp. setup, tie-downs & hitch exten?

On the hitch. Curt makes a Class V 17,000 lb hitch that will bolt under the factory hitch on the Dodge. I've used this in the my 2011 and the 2012 3500 to tow my Bass Boat which is a little over 3500lbs, using a 24" extension. I then bolt the factory and the curt hitch together for a very heavy duty setup. You can find this hitch for less than $250. I have less than $350 including extension and ball.