I have a 2014 Journey 3.6 and it has overheating issues too. Coolant leak which dealership said may have been a loose radiator cap 2 weeks after i bought it used from a local dealer in 2015. 2 weeks later overheating again lead to blown head gaskets. Warranty covered all work required luckily.
Now guess who is acting up again in March 2017. Coolant leaked out of reservoir with temp. needle bouncing around. Took car into dealership and they pressure tested system and stated it may have been a loose radiator cap but found nothing wrong. Does the cap just vibrate loose or maybe whomever did our last oil change and checked fluids in late January 2017 didn't put it back on tight? I don't know. Maybe in 2 weeks I'll be getting extensive engine work done again.
