I too have an '04 4wd Hemi and have pulled a 24' enclosed trailer with my Hemi Barracuda inside and a 28' enclosed trailer which was taller than the standard trailer with the same car inside. I went from Indy to Columbus, Ohio both times and didn't have any problems. Didn't check the gas mileage because I didn't care, I figured it got what it got. The Cummins diesel would be far superior but for my daily work truck the Hemi does just fine. Hey, does that Hemi have a Hemi? Yup.