VIN reprogram with 3.0

[scattergun9]

Is there a VIN reprogram feature with 3.0 or am I just not seeing it? Also Is there a sure fire way when doing a VIN change only on a Gen 4 and 5 PCM? I have had issues with the Vin reverting back and not changing on gen4's. Sometimes leaving the key off for a long period after the vin change does the trick but not always. I also use Tuner Gato and GM TIS and have had the same problems with all. Im currently stuck on my own personal 2016 z71. I bought a used PCM and reprogrammed it, got the VIN to change from a 2015 to my 2016,but then had the IMMO be locked out and not program no matter what and since there isnt a vats delete yet on a 2016 OS I was up shit creek. I then programmed the PCM as a 2014 with vats deleted and it ran,but had invalid communication issues to the EBCM setting codes and reduced power issues intermittently. I then reprogrammed the PCM back to the 2015 VIN and OS I started with, and magically was able to do the IMMO learn and my truck started and ran, even on the wrong 2015 VIN. Weird, so i am on the right track I think, and reprogram it back to the 2016 OS, but now the VIN is stuck on the 2015 and no matter what I try I cannot get it to change again. The TCM shows correct 2016 VIN. Any Tips would be greatly appreciated, Ive wasted hours upon hours now. My concern is I havent activated Onstar yet and would like too but worried they may see the wrong VIN and tell me to take it in.

[scattergun9]

Sooooooo, I got it. I reflashed to the 2014 os again. I was now able to do the VIN rewrite and it actually took. Then full reflash back to the 2016 OS and The VIN is correct. After 2 days of messing around, Ive learned that 2015 and 16 operating systems are different than 14, If your going to get a 2nd PCM for a 15 or 16 and need to do immobilizer learning, just buy a new blank pcm,they dont cost that much more than used and you shouldnt have any of these problems. If you do a gen 5 swap, just go ahead and program the pcm as a 14 to delete Vats. If you do get a used pcm for a production vehicle, flash it to a 14 to do the Vin change first, then put in your desired OS,but first learn the IMMO before doing anything. Well at least I feel like i have contributed some useful info to this forum.

[scattergun9]

Also there isnt anything different between 14, 15,and 16 E92 pcm's just part # changes, Its all in the OS's