I work on these almost daily at the dealer. I also have a 2016 Durango with the 3.6 pen taster upgrade. They are generally a good engine but we are still seeing roller rocker failures occasionally wiping out cams. I think keeping the oil changed frequently and keeping the idle time low is the answer to that problem. Have you opened the hood on one of these new Jeep’s Rusty? Not very Tech friendly, they really stuff that engine bay tight! Not very do it yourself friendly for those who like to do their own work