I don´t know to much about the oil history. But here in extreme south Brazil, were I live the temperature jump and dive along the year. In the summer is very hot and in the winter is very cold. The point is I try to use all the oils avaliable in local market and believe or not, the best result I had was a TWO STROKE MOTOR OIL. Yeah! 2 Stroke oil! It is thin enough to works fine when I start up the engine in the winter. But I need to do some changes in the oil system to avoid the pressure loss.
