Since I had my DEF heater replaced I have had zero issues in over 25,000 miles. I haven't even gone in for the last sensor recall since it was done once (or twice?) prior and the car is running fine. Does this mean that the DEF system is now under warranty for 100K or lifetime??? Also, are they (GM) recommending taking in your car for the recall/replacement of the system no matter what? I'm confused. I can't read what the OP posted as an attachment.