Yeah the emissions stuff is getting out of hand, what are you getting MPG wise? We're seeing 11 with our 6.4 and around 14 with our 6.7 I read in another thread guys are seeing around 7.5 loaded with a gasser. We average around 20k miles per year (not including reverse while plowing lol) So doing some rough math and a life cycle of 10 years it's a fuel difference of almost 37k in fuel. This was the main reason we switched our mower fleet over in 2011. Maybe my math is a little fuzzy but if it's even close that is a huge cost savings.