There's nothing like the pulling power of a diesel. You might not need it all the time, but when you do you're happy it's there. My truck weights a little over 7k and I average 23 mpg on the highway (empty), and that's with all the emissions intact. The best I could ever get in my '07 Duramax was 19 mpg, and that truck had all the emissions gone, economy tune and weighed 1k less. Last year I relocated from Ft. Richardson, Alaska to Ft. Lee, Virginia. I pulled my 24' enclosed trailer full of my household goods and furniture. Going across the scale fully loaded my rig weighed right at 17k. The bottom end torque was so nice when I was crossing the rockies in northern Canada, and during the whole trip (which took six days) I averaged 13.5 mpg. If you ask me every vehicle should be diesel.