Have a 2015 GMC Sierra SLT. Have tuned the trans a good amount and that is running great. Previously took my truck to a tuner and he said he adjusted fuel trims for the headers, driver demand, and timing for 93. He didnt do a lot of things that i asked him to do on the trans side, so that makes me skeptical if he even did anything on the engine side. Wanted to see if anybody can suggest best ECM tuning to add to my L83 that has a oem non dod cam for performance and reliability. Tune attached below. 2015 GMC Sierra Beta.hpt