EFILive tuning for the 2015.5-2016 Duramax is now available to meet your desired horsepower gains. Each AutoCal will come with 5 tunes. When you purchase a GDP Tuning AutoCal you will be ready to unleash the beast that’s locked inside of your truck.
2015.5-2016 6.6L Duramax tuning comes as 5 separate files. To change power levels you must re-program your vehicle with the AutoCal.