I want to reprogram an ECM on my denali to give it more power and remove the AFM. My plans are to buy another ECM, program it and swap it out. The service advisor (friend) said that GM can tell that I have swapped the ECM and will void the warranty. Can anyone confirm that? Thanks in advance!

 

He is right.

All of the newest controller from 2014+ in those trucks can tell when it was programmed, when it was last flashed with something and it will void the warranty on the powertrain.

 

Three places the vin and milage is stored.

Ecu, instrument cluster and bcm. Possibly even in the onstar module.

Makes it almost impossible for even the most tech savy tec to play with the milage and vin.
Thats why all modern vehicles that are stolen are stripped for parts or sent to mexico.

You wont find a modern stolen vehicle on the road very long if at all.

 

All of this data is retained in the calibration event data section on the E92 ecm. The process for hard part replacement in the engine or transmission requires saving a copy of this information and a copy of the Calibration verification numbers to validate there is no modifications. If The tech knows anything about this stuff you will most likely get caught but most techs have no idea about this stuff and don't even know where to find it. It's sad but it's true. So yes you can get caught but I doubt you would as this requires more digging than most are capable of. Denying warranty claims sucks for everyone and is always a war. I have only had to do it one time. This customer drove 5500+ miles with an engine that was overheating and the last failure was recorded at 88mph and at 80% engine load, the pcv hoses were completely melted, no to mention complete and total neglect of maintenance. Bad situation all around.