not sure about no load but it get up to 2100 when it shifts, I have a 12 speed ZF/Meritor Smart Shift. I am 42, long tow a Jeep Liberty and we wt in at 34,500 to 800 depending on the water I haul. I cruise at 65 mph and turning 1500. 7.5 mpg, Not much on the idling and running the genset. Ask...