The H&S Mini Maxx will not work on a 2015 truck. For some unknown reason people purchase the Mini Maxx thinking it will work on a 2015+ GM Duramax. It will not. The Mini Maxx will only work on the 2011-2014 LML Duramax. Check your VIN before purchasing. The 10th digit will tell you the year. 2013 = D, 2014 = E, 2015 = F, 2016 = G. The pic below is the screen you will come across if attempting to install on a 2015+ model year truck.