My son has 2014 RAM 1500 with a eco-diesel. A couple of weeks ago a code came up which said there was a fault with the thermostat I don't remember the code number. Wanted OEM part and since none of the local dealers had the part we ordered the thermostat from Rockauto. We also ordered a radiator cap from rockauto the original one was not coming off when it was unscrewed, something not quite right with it. So a new cap was ordered and it was not OEM. So now there are times when it works just fine. Otherwise it will spill coolant from the over pressure hose on the coolant tank. No rhymn or reason to when it will spit out the coolant. Wondering if I should be trying to track down a OEM coolant cap. Temperature is running where it usually does. Just a note I'm not a mechanic but have owned a few ford's so have gotten my hands dirty a few times.