I’ve always wanted one of these 30 mpg eco diesels since I read those initial articles about 10 years ago.  I found a 2015 Laramie 4x4 in perfect condition and full history of recalls and warranty work.  Later learned it had a GDE engine, trans, brake, and regen tune. I’m optimistic as I need this truck to last at least another 10 years.  Learning as much as I can about maintenance on these motors with help of the forums.