I took my truck in for work (steering shaft and P0802 code) and I don't know what they did, but my exhaust is much quiter and I am getting better than 21mpg on the highway. Up from 18. I have not put my juice back in as I am very happy with the mileage right now. It didn't say anywhere that they updated my truck and I didn't ask but as soon as I pulled out of the dealer I wandered what they did because my exhaust was noticibly quieter. I can barely even hear it now and I was thinking of putting my stock back on because the MBRP was too loud. Then I started driving and looked at lie-o-meter and it was telling me 22mpg. I haven't hand calculated it yet but I know I'm getting better, as I have gotten more miles on 1/4 tank of gas then I had in the past. Anyone else seen this? I didn't even know there was a flash available.