sheriff dog - have driven the new 6.7 diesel and was impressed, even though I already drive a cummins. Have not driven the gasser yet and may be equally un-impressed with it. Will either be going to Asheville so there are some true hills to climb or will be using a local route over two 200' tall steep bridges.
I also went back and looked at a spreadsheet I've been working on to discover I had a formula error. Changed the numbers enough that I'm having to study them again and re-evaluate my decision though doubt it will change.
I use to drive a Ford F350 Crew Cab 4x4 with the 460 and 4.10 gears. Used it to tow a 7,000# TT and only problem I had was in Nebraska fighting a 40mph head wind. Had to slow down to 50mph but did fine other wise. Also grew up camping in a TC with an old '69 Dodge Power Wagon and small 318. Never had a problem with it either. Gasser is going to be slower, but that is my driving style any how.