I bought a 2013 ram gas 2500 hemi last summer. I looked hard at a diesel but decided the overall cost was just too darn high.
It is a 5.7, so smaller than your 6.2, and it pulls my 8000 trailer fine. On level ground I get 10-11 mpg....in hilly country I surely get less, but it pulls well. Does it stroll Lee on steep hills?? Yep, but not nearly as bad as I would have expected.
The point is, today's gas motors are better than ever an the cost of the diesel, the maintenance costs and higher fuel costs make gas motors a viable option.
If I towed thousands of miles a year or if I was in really hilly country,I would have bought a diesel, but I just don't need our want one.