ib516 wrote:
I truely believe (and studies have proven) that driving style can vary mpg up to 30%. My wife consistently gets less mpg in the same vehicle than I do. She's on the gas until she needs to brake, and I coast a lot more and look further down the road, she takes off more aggressive than I do too. That's just a couple minor examples of how a person's driving affects mpg. I'm pretty easy on my stuff when I can be, but -- when I need it to perform, I let it rev and push it.
I'd believe that a 2 (on the low end) and 4 (on the high) is about the mpg difference between the 6.4L Hemi and the 6.7L Cummins. But, remember that the Cummins makes 370 - 385hp and 800 - 900tq and the Hemi makes 410 hp and 430tq. That's a big tq delta.
The driver makes a huge difference. My wife and I have the same exact situation. I really have to bite my tongue when I ride with her.
Fuelly is probably a pretty accurate gauge on average mileage because you've got enough people submitting info that you're going to round out a pretty good average of what the vehicle is getting real world. From that point, I'd agree you can probably take it 25-30% in either direction based on driving habits. Fuelly might actually penalize the CTD a little bit extra as I'd wager your average trailers are a little bigger and your towing % is a little higher with the diesel.
