ive driven this truck unloaded and my stock 7.3 would smoke it with no problem.it just had a motor put in it with the headstuds,brand new,not remanned turbo.it has no sack.hit a hill doin about 70 with your foot to the floor and its working harder than hell to keep up to speed but dropping speed.the driver is driving it right.i wont drive it with a load on it.im not gonna be the one to pop the second engine.if it was me driving it today i woulda pulled over on the highway,put it in park and held it on the floor till the motor blew.thats how bad this thing is.ill never buy a 6.0
but enough with that.there has to be a way to get some more nut and better fuel mileage out of this thing.it even drinks like a fish with no load on it.my tweaked 7.3 gets better fuel mileage in the wildman/luke cline extreme wich is a nasty program.