I went from a 07 Chevy 3500 DRW duramax to a 2018 ram 3500 DRW 6.4 mainly because we are carrying a TC instead of towing a 16000 fifth wheel but the main factors in going with the 6.4 gas and not a diesel were many of what other have said, the cost of over 10k more plus the transmission upgrade and the complexity of the new emissions on the diesels . The truck I ordered is 6.4 hemi with 410 gearing and could tow a 15k fifth wheel and has almost a 7k payload which is what we needed for the TC . The ram only has 2k miles on it so far ibut the mileage with the 410’s is not great around 14 with out a load so even with the eco mode the 6.4 is thirsty , hoping it gets a bit better but the truck is not a daily driver so it’s the price to paid to carry a heavy TC