No problems here pulling livestock trailer. Normally in the 6-7000# range. Do tow 10,000# rarely on backroads (just because that is the best route, wouldn’t be afraid to take it on the highway if needed) at around 50-55mph no problems (could go faster but the roads are too rough). Power and acceleration not an issue, I also have rear in coil air bags that help tremendously (obviously I do not have air suspension). As for mileage, I really can’t say, sorry about that. I generally hook to the trailer, load it, tow less than 30 miles or so round trip, unhook, then maybe do it again within a few days. Not consistent enough to get a good, accurate mpg for you guys. I do not want to go off the instrument readout as the trips are too short and my speedo is not calibrated for the 35’s or the 34’s I currently have on that I run in the winter. When I make a longer trip I will have to do the mpg’s on paper. Good luck!