The biggest problem I heard of with them, (this was back in 2015 when I was considering one in my Grand Cherokee), was the timing sprocket on the camshaft was pressed on, and not welded. This caused issues with many engines, when the sprocket got loose and started to slip. I don't know if they corrected it or not. I know they stopped offering the Ram pickup with the Eco Diesel for a brief time. I think there were several other issues with that engine as well.
I was also considering buying a 2017 Ram Ecodiesel as they were basically giving them away, however I changed my mind because I didn’t want a turd and bought a GMC Canyon Duramax instead.
The timing sprocket isn’t a real issue. There is a YT video of a guy rambling on about it but it’s rare and not one of the common failures with this engine.
The main cause of engine failures with the 3.0 ecodiesel has been big end and rod bearing failures. FCA changed the oil spec to CJ-4 and also reprogrammed the TCM to limit lugging which helped but also reduced the advertised FE by 3-4 MPGs. Another cause of oil related failures is the cheap oil cooler which is prone to leaking which also contaminated the oil causing engine damage.