mate ive got the 2011 2.3 multijet the motor is pretty well bulletproof i got 750000kms out of mine and spun a big end bearing ,the clutch is the weak link the torsional springs are too large and do break out at the 2000000km mark, the gearbox despite what fiat says should be drained yearly it only takes 3 litre so its not a big cost,cover any and all electric terminals with silicon/electrical grease despite what people say that engine cover causes as many problems as it solves as it creates a warm humid environment underneath it which adds to the water ingress and seizing of components ,spray the injectors regularly with wd40 or equivalent to help prevent this but then again i got 720000kms out of mine and id keep on using them,on top of the engine is a long plastic trough with an exposed wiring loom passing through it keep the trough clean the lid just pops off and you can wrap the loom in electrical tape to help with any further issues,fuel filters can be a pain to change and you will find a plethora of posts on how to change them here,cooling fans can be an issue an easy way to check is when you get a check engine light the remaining fan will keep running after the engine is stopped for 10 seconds or so ive run mine through necessity with both fans not working at 90km/hour in 45 c degree heat and it doesnt over heat ,im still running the original drive shafts and front wheel bearings with over 900000kms on them,turbos are good for at least 600000kms,front struts are good for 350000kms,and lower ball joints around 300000kms ,brake pads last me around the 300000km mark on the front and 400000 on the rear,
mind you i am in Australia and i dont have the same winters and salt that you have but i have buldust and mud my vans been all over Australia including the Tanami and Strezleki tracks fror the heat and humidity of the gulf country to the snows of tasmania its been the most reliable vehicle ive ever owned after we sorted out the teething problems but thats another story drive it hard its a comercial vehicle and enjoy it
Cheers Adam