I have 800 miles on my rebuilt 235, with SM420, and 6:17 rear end.
Most of my driving has been stop and go, sometimes hauling 4-6k in town, top speed of 50.
The truck is a LoadMaster 4400 stake bed, with dual rear wheels, and weighs about 6000lbs.
When we rebuilt the motor we went to standard crank bearing inserts, aluminum pistons, and stock style cam.
I have been tracking my fuel economy for the last two tanks, and so far I am averaging 6.5mpg.
