It will kill some of your power because now your truck has to not only tow a trailer, but has to turn the bigger wheels you most certainly have on it. I think you can fix that by changing the gear ratio in the axles..but that's more money.. not to mention the more you lift, the less stable the vehicle becomes (top heavy).
Also those newer dodges get crummy mileage as is (supposedly until they "break in" at 40,000ish k miles)..
Everyone I know who owns one (diesels), regrets getting these trucks because instead of getting 18 to upwards of 20 pulling a trailer with a model just a few years older, these new cummins are getting a whopping 13 highway/empty.. why you would willingly make that worse is beyond me:)
I have an 06 cummins, that I put just and inch taller tires on, and that has had a profound effect on my fuel mileage:( went from getting 18mpg to 14/15 pulling a trailer..