Hi in AZ. The Classic is 18000 empty, 20000 loaded.The 5.9 is rated @ 230 hp stock.It uses the Allison md3060 6spd.W/ 5&6 being overdrive .
Cummins reccomends 100h.p. per 10,000 lbs. We have been all over the western states on our summer job & kept up with traffic @ 75mph.
we tow a jeep wrangler 4000 lbs.
In the real heat ,I have to watch temps ,water & pyro,in fact one of my spring projects is to pull rad.replace with bigger ,better ,elect fan,engine oil cooler & whatever will help with problem .
The 5.9 cummins is a proven engine ,that will make lots of power,more power more heat,getting the heat out is what I need to work on , any suggestions would be welcome. Welcome to the forums & hope you find a good one. Phil & Sandy. Christmas Valley, Oregon