We had a 27 ft. 2008 R-Vision Trail Cruiser TT that was 4200# and towed with a 2008 GMC Sierra 1/2 ton 5.3 V8, 4WD, it seemed to pull fine, last winter we traded the TT for a 2012 24ft. Jayco Jayflight that weighs 5300#, the first trip with the new camper I immediately noticed the truck was quite underpowered, the frontal area on the new camper is more square so I guess that is why the camper pulls harder, I did not think 1000# would affect it so much, I have worked for GM dealers for 25 years so I am partial to GM although I am sure all the others are great too, any way I went to my salesman about buying a 3/4 ton with a 6 litre, I really didn't want to go the 3/4 route because I tow a small snowmobile trailer all winter and a larger truck would be overkill, My saleman informed me the new GM trucks with the 5.3 engine with variable valve timing and 6 speed transmission is rated for 9500# towing capacity so I took the plunge bought a 2012 Chevy Silverado 4X4 extended cab and he was right, the new configuration (6 speed trans and reconfigured engine) is much more powerful than my old one, it also has an integrated trailer brake and stabilitrak that will engage the trailer brakes should I start to jack knife. I couldn't be happier! the truck does about 9MPG towing the TT, and will do 21 - 22 MPG empty.