2006 Chevy 2500 HD w/ Duramax Diesel. Crew cab and 6.5' bed with shell. Original tow vehicle was a 2004 Ford F-150. We live at 6000' in Colorado and the Ford struggled on the passes. The Duramax seems to disregard the 2000 lb. trailer and gets much better fuel economy. HUGE power !
If you're going to use a truck as a tow vehicle, consider a diesel,,any brand and no matter how light your trailer is.