I tow almost 10,000 toy hauler bumper pull with a 2014 Ram 2500 4x4 5.7 Hemi. I typically run 65 to 70 MPH without a problem, some of the Western Mountain roads suck me down to 55 or 60 MPH. Gas milage runs between 6 to 8 MPG depending on the amount of hills and Wyoming head winds.
2015 Eclipse Iconic Toy Hauler made by Eclipse Manufacturing which is a pile of junk. If you want to know more just ask and I'll tell you about cracked frames, loose tin, walls falling off, bad holding tanks and very poor customer service.