I have the Bully Dog also, and I usually get about 16.5- 17 mpg in the city and around 19-19.5 on the highway if I drive nice and under 2000 RPM's 65-70 MPH. I run it on the performance mode everyday driving.Airaid intake,4" MBRP turbo back exhaust,Outlook monitor and Autometer EGT and Boost...