A lot of people think that a 0w30 oil is overkill, especially if the area you live in doesn't get much below freezing too often, but you can definitely see lower startup oil pressure with a 0w oil compared to a 5w or 10w oil. This is a major benefit, as it will allow your oil filter to get out of bypass mode much sooner.
And as Oldswagon mentioned, the oil pressure moves up faster on the cold start, indicating the oil is flowing quicker than the 5w or 10w oil he was using before.
I've definitely noticed both of these things in my Firebird since switching to 0w30 from 5w30. My wife's Honda has no oil pressure gauge, but as I mentioned in another thread, her engine is much quieter on the cold starts now with 0w30.
I think 0w20, 0w30 and 0w40 oils are the wave of the future, and we'll be seeing more of them introduced in the coming years.
It's all about the flow man!
[ October 20, 2003, 09:51 AM: Message edited by: Patman ]