My brother in has a 2018 RAM 3500 single axle, with a manual transmission, I have a 2018 Ecodiesel,
He sees 20-21 MPG on the highway at 70, I see 23+,
Having towed 12000 pounds+ with my ECOdiesel, and it did it without breaking a sweat, although trailer brakes are required! (I maxed out at 40...