What does a full os flash entail? I don't believe I have heard that before. Does the starter tune on the flash scan allow for deletes? Could one possibly pay for a custom tune that would normally be on the autocal and have it put on the flashscan or are those tunes proprietary to the tuner?
OS = operating system.
The popular aftermarket tuners (Smarty, H&S, etc.) do not put a true factory flash on the truck. It may run exactly the same, but the file isn't exact, so you often get a checksum error when scanning the computer after being returned to stock by one of these tuners.
An OS flash means you're completely reprogramming the ECM with a COMPLETE "clean" (correct/valid checksum) program vs. scanning and modifying what is on the ECM.
Please forgive my ignorance if Autocals come with full flashes as I have only ever used a V2