I HAVE A 2013 GMC SIERRA 5.3, I HAVE THE INTUNE AND IS PROGRAMMED RIGHT NOW AT 87 OCTANE AND FIRM SHIFT, IT SEEMS TO BE THAT THE TRUCK DOESNT HAVE ALOT OF POWER LIKE IT SUPPOSE TO I GUESS, I ALSO TRIED THE DIABLO 93 TUNE. THE TRANS SEEMS TO SHIFT FAST AT LOW SPEEDS AND IT SEEMS LIKE IT TAKES ABOUT A ...