Originally Posted by philbytx
FYI - The VM Motori diesel does not have a viscous coupled fan on the motor, just a large electrically operated fan.
After some more digging, I found this answer from Jeep engineering to a question on what kind of fan the Ram 1500 Ecodiesel pickup used:
Bob Hegbloom, Director of Ram Truck Brand and Mike Cairns, Director of Ram Truck Engineering answered questions in an open Google+ Hangout on June 12, 2014.
"Electric or mechanical cooling fan?"
- 800 watt electric fan that can operate at variable speed.
Pretty efficient cooling when they can use about 1 hp of electric cooling on a 1500 Ram pickup truck. At 14 volts, thats about 57 amps of power being used by the fan at peak levels, so it doesn't seem likely that they can increase the fan speed by very much.
I did read one review of the Ram 1500 Ecodiesel where during towing 5000 lbs at high altitude the coolant gauge reached 244*F shortly before the summit. IIRC, it was Diesel World or DP magazine.
I see the good news is that with both the Ram 1500 and GC using an electric cooling fan design on the same engine, there should be enough engineering attention from the Ram/Jeep team to address the calibration issues.