I dont know anything about the Ram but I do know about the 6.2 Ford. The wife and I are are on the return leg of our second round country trip with this truck and fifth wheel , perfectly reliable so far and I have filled up twice a day on average. This year I have kept the speed to about 55 - 60 mph , by the time we get back home to Ontario it will have logged a little over 8,000 miles /13,000 km in just over 4wks , we left on the 10th jan and will be back on feb 2 we do about 10 to 12 hrs a day when on the road and are currently overnighting in Texarkana.