X2 fisher guy. For me, with a trailer very similar to yours, I find the 3/4 ton diesel the only way to go. I live in S. La. and it's flatter than where you are. Have towed smaller, lighter trailers with 1/2 tons and yes, it moved them from point A to point B. The overall performance of the rig IMHO is well worth the extra initial investment. My Cummins chugs along @ 2000rpm @70mph. In W.VA a couple of weeks ago, we hit a 9% grade about a 1 1/2 - 2 miles long, 60 mph @2000rpm in 5th gear:awesome! My experience is that a gasser is going to hum at a much higher rpm., use more fuel, strain the tranny, rear end, brakes and suspension. Since I grudgingly went to the diesel two trucks ago, I will probably never get another gas truck. I went to one vehicle dealer and he guaranteed this 40hp riding mower would pull anything! LOL Anyway, best of luck with the new truck, whatever you choose
