I have had several 6.0 HD's. I had an '11 and a '15. The '15 had 4.10's, the other was 3.73's. I routinely weighed 31K combined with the '15 moving equipment. There of course is little wind resistance verse pulling an RV. The truck though would pull up passes up to 8K, slow and it would rev, but I thought it did very well. I would not have taken it up Teton Pass that heavy but short of that I felt comfortable pulling it at that weight. The diesels are better without question, but the 6.0 is very capable gas engine.
