Mitch - Lol - maybe I'm asking too much on the mileage!! It pulls so well that I kept forgetting the trailer was back there - we're now 1000 miles further into our trip,and (excluding the pull through the Great Smokey Mtns) I've got the average up to about 12.5 Highway with the trailer on the back, mainly by adjusting driving style.
The problems I had with the Durango were less with power, more with the transmission - overheating, slipping gears on long hills. The F-150 handled a 5000' / 20 mile climb last week with barely a twitch, so I was very happy with that. Transmission temp increased from 195 to about 225, which barely moved the needle from center. Not sure what the max is on the transmission oil - anybody?
Redline - I hope not, because its too late - I've got the ecoboost now, and so far, very happy with it.
Appreciated all the input on this one a few months back, so thought it was only polite to let you know where we got.
Ended up with the F-150 Ecoboost, and loving it so far.
We're now 1000 miles into our 4000 mile summer trip and it is pulling like a dream. I've ended up with a very stable rig even in strong crosswinds during the storms we've had this week. The ecoboost engine has bags of power from low down, and its taken the hills with no problems at all.
The only slight disappointment has been the gas mileage - currently averaging around 11 with the trailer on, 15 around town and 22 highway as long as I keep it to 65. The disapointment comes in if I increase to 75, when the mileage drops way off, and I mean waaaay down - 17/18 sort of territory which is a big hit for 10mph.