The E41 controller modification service will allow you to use the aftermarket tuning suite of your choice to modify your E41 equipped 2017+ L5P Duramax.
This is a service performed on your original ECM with a 1-2 business day turnaround.
You will receive your original ECM back if you choose "Upgrade My ECM". You will not have to perform an immobilizer relearn or any other relearn operations before you reinstall the ECM in your vehicle.
Choose "Purchase a New Upgraded ECM" if you need a spare upgraded ECM. This will require you to resynchronize your vehicle's immobilizer to this new ECM.
The ECM operating system and calibrations are not modified in any way from OEM stock, and retain the original OEM CVN's.