What is the point of using 5 or 10 w30 when 0w30 is available? I've made up my mind that 0w30 is the way to go year-round. I'd like to hear what you guys have to say. The only reason I can think that 5 and 10 w are produced is that not all base stocks measure up to the 0 grade and it really isn't quite so necessary in warmer climates. I know 5w has very good cold weather performance but 0w is better and the latest oils don't seem to shear. I think 0w30 is the best regardless of brand. I can understand why the oil companies wouldn't want a run on 0w30 - I don't think the production capacity is quite there for that given the rationale above. What do you guy's think?!