It seems many people are suffering from not really understanding the terminology or the properties of the oils that we are interested in. This is a good site to educate ones self:
Very good site describing properties of oils. I spent some time dredging this stuff up for people because I for one am tired of getting ripped on for choosing a thicker oil
I believe that I am choosing correctly because I took the time to evaluate the operating temperatures I actually run my car in. A 20w-50 oil is NOT a 50 weight oil. It is a 20w oil that in 100F ambient temps will provide a better oil barrier on the bearings than a 5w oil. For the last time... it doesn't thicken up or become more like a thicker oil when it gets warm! None of the oils do that. The additives will keep certain properties behaving like a that of thicker oil, but not the thickness of it.
It pours good down into the sub freezing temps, below 30F, but it would not be my oil of choice if my winter temps were below 35-40F consistently. It is not what I run in winter anyway. With winter time I've run a 5-30, 10-30 or a 10-40 depending. In AZ and TX the winter temps rarely got below 45-50F. Hell in AZ my lowest winter temp was about 55F during the day and 30 in the middle of the night.
I like the advice to use the narrowest multi-grade oil corresponding to the temperatures the car will see.
I say this knowing that I change my oil frequently and that because of the frequent changing the thermal breakdown problems of dino oil are less of an issue.
I choose right now to change oil more frequently rather than use a higher priced synthetic and run it longer becuase I feel that there are too many contaminants introduced into the oil over a long term that will not be filtered out, despite whether the oil remains good or not. With a turbo I will have more risk so I change the oil every 3-5K miles.
Why would anyone trade away the bearing protection that a thicker oil can provide, IF the thicker oil can pump well enough on startup, not be so thick that it creates serious drag, and still flow well with plenty of sheer strength at high temps? Aren't we using our engines once they warm up to high temps?
Hell, as long as the oil can pump through to the top end quick enough on startup, then I have no problems letting the car warm up before getting on it in order to have a thicker oil to prevent thinning problems at operating temps.
