Does Max Torque = Max Efficiency = Max MPG?

[frizfreleng]

Power curve on my 2004 6.0l puts max torque (560 ft/lbs) at 2000 rpm. Read in an RV forum that max efficiency is attained at max torque for a diesel. Looking for the sweet spot for hour after hour of interstate driving pulling the 5th wheel. My truck hits 2000 rpm at 70 mph.

Thanks, Friz