I think for stock set up 40-45 cruise is the sweet spot-
you run 50- just takes a little more fuel. I have a 216 in a 3/4 ton, and a 216 in a 1/2 ton. the half ton is a little better at 50 than the 3/4, I think because of weight, gearing, etc. But I have taken some decent drives of 250+ miles in either truck and they will cruise all day long at 40-45 without a hitch.
At 40-45 I avg around 18mpg in the 1/2ton, about 16-17 in the 3/4, when I get up to 50, both seem to clock in around 13-14.
My folks have a lake cabin about 108 miles away from where I live, and I am not worried to take either truck there and back on a nice day(which is any day in my bolts)
