Third Generation Duramax Electronics/Tuners
I have EFI live in my 06 LBZ.
I wish to re-Flash my ECM with a Stock GM Tune .
THAT In itself will not be an issue, have good friend - Diesel Tech at local GMC dealership.
What I'm curious about is that I have the 5 position Switch...and what do I need to do in regards to this..??