If the oil doesn't get hot enough, water will build up in the oil because heat is what helps it evaporate.
Oil with water is corrosive and also depletes the TBN of the oil which leads to sludge buildup and acidity. The LL04 oils have weaker TBN than dedicated HDEO diesel oils.
Why didn't those idiots could have updated the dde to report thermostat issues? It can be detected by a simple algorithm based on external temperature, fuel usage, and time.
Last edited by robnitro; 03-06-2019 at 12:45 PM.