Hello everybody, I’m just posting this question in this forum, because that’s probably the most appropriate thing. Oil is somehow also part of vehicle maintenance, just from the inside I’ve tried to get smart from the two digits of a multi-range engine oil (e.g. 10W-40). So far I’ve found out from Wikipedia that the first number probably indicates what viscosity the oil has when it’s cold (ca. -18°C, is that right??), the W stands for winter, and the second number gives the viscosity of the oil at approx. 100°C. The higher the viscosity of the oil, the thinner it is, right? And thinly liquid the oil should be, or does that deceive me?? If so, how can it be? Why is 5W-XX oil better than 15W-XX oil, if it is actually thinner in cold?? I have read some of the additives and synthetic oil that should protect the engine inside, but at the same time a low viscosity should be less fuel consumption of the engine before the W. But how, if the oil is actually thicker than one with a higher number. I stand absolutely on the hose with it. Can anyone explain this to me?? merendo