Has any experienced derate issues of the current Duramax diesel due to DEF sensor issues? With other makes, it's a big issue with derates to 5% when the sensor fails regardless of tank level.
Asking for advice. I live in the Phoenix area and am trying to get into a Sierra that I want to spec. It would be the first vehicle I’ve ever bought not off the lot.
The issue I have is getting a dealer to respond. Or in some cases to be both transparent and communicative. Does anyone have a dealer recommendation?
If anyone is interested, here is the link to the build.
2021 SIERRA