3.42 or 4.10?

I was on the Ram 3500 2013 build your own site. Now I have had trouble with these build sites for all of the auto manufactures so you can not be sure if the information you get is correct or not. But if I choose the 6.7 high output diesel with the Aisin 6 speed Automatic the only axle ratio it will let me choose is the 3:42. But in my thinking with the 850 ft lb engine and the torque/hp curve it has the 3:42 should work very well.
Has anyone received a 2013 3500 Ram with the Aisin automatic. If so what axle did you get?