Hey guys, just wanted to make a post because I could never find one as detailed as I wanted on what to expect when towing.
Yesterday I towed a 7x18 car hauler with a 1982 Ramcharger on it from NH to VA. About 12 hours overnight, stopped for fuel 3 times just to make sure I didn't go below ~1/4 tank.
Driving a 2018 2500 crew cab 6ft bed, I ended the trip with an average 18.1 MPG with cruise control set at 55 MPH. I have an MM3 from Double R Diesel running the 30HP tune and was monitoring ECT/EGT/trans temp the whole way. I'm also running a 95GPH FASS pump with a Beans sump draw, and S&B CAI to match the 5" turbo back. My highest EGT reading was 999.5F going through the big hills of Connecticut on the highway on the way down. My coolant maintained roughly 192F, and my trans never went above 170F on the road.
The biggest tip I can give that I know is common knowledge is to tow in a lower gear to maintain about 1600-1800 RPM. I was using the "manual" shift to switch between letting the truck go to 6th and keeping it in 5th gear and couldn't believe the immediate difference in EGT readings and smoother boost going up and down the hills.
I'm sure this is common knowledge as I said, I just wanted to provide more details and hope this helps out someone looking for information. Remember to keep your tow mirrors out too for extra HP