I'll chime in here. Three days ago I bought a 2500 HEMI 4wd. When I first drive the truck I was really impressed with the power, and I just got rid of my 2005 with Edge box. SO, I bought the hipe of the HEMI. I towed with it once (6000lbs) and took it back today to trade in on a HO Cummins. I could not get better than 10. 4 mpg towing no matter how conservative I was. Even worse, I had to put in premium fuel to keep it from pinging on the hills, which negates the cost of fuel!! Even in town, it sucked fuel. After owning Cummins for the last 15 years I should have known better, but was trying to save a few $$$.
If you are concerned about fuel mileage a gas engine pickup will not be your solution. A gas engine will provide slightly better fuel economy at steady highway cruise speed unloaded. Around town driving or pulling a trailer it will be no better and with a heavy trailer it will be worse.
Gas mileage is only a part of overall operating cost. Long term durability and resale value are also factors and an area where a gas engine will not compete.
I know the reasons to own a CTD, i have owned my current truck sence December of 98. I was just looking for a comparison of fuel useage of the new 6. 7 trucks compared to a comparable truck ( 2500,3500) equiped truck with a Hemi.
Not to start a fire, but how does a 2010 6. 7 compare to the same truck with a 5. 7 Hemi as far as fuel use goes? I am looking to move up to a newer 2500 or 3500 crew cab 4x4 , and with fuel prices heading up again, i need to consider all choices. THanks for yuour opinions, Randy.