Hello, new to form and was curious about what others are using for oil in there tuned golf r's. I have down a lot of reading on here and opinions appear to be mixed. I live in Canada where it can go from -40c in the winter to +40c in the summer. I have been using motul 8100 excess gen 2 5w40. From what I read castrol 0w40 would be a good choice and would be of benefit for cold starts being in Canada. Although the car is tuned I don't track it. Little spirited driving here and there nothing extreme. Anyone use 0w40 year round or would 5w40 still be a better choice for the hotter months? Thx in advance.