Moderator: volvite
I agree with the new lower weight oils are fine although I would never run a 20 weight oil in my VQ not that it would not work esp in the valvetrain area and bearing area. With the VQ 40 I really think they need a solid 30 weight for the timing chain area. Over the years I have seen where heavy oils 30,40,50 weight oil seems to show less wear in engines small to big in the timing chain area. I will say that Mobil 1 0W40 runs smoother then anything in my Pathy. M1 0W40 is (Just a 40 weight) meaning that it's running viscosity is just over 30 into the 40 range. The way I look at it is if under load a 30 weight oil may shear down to a 20 weight but M1 0w40 will only drop down to a 30 weight.smj999smj wrote:Actually, the thinking of late...and this issue was just discussed by Blackstone Labs...is that thinner oil is the way to go. Thinner oil is easier to pump and lubricates better and despite what many of us heard over the years, it is very rare for oil to break down even under heavy duty use. Even heavy duty trucks, which for a long time were using 15W40 oil, are starting to see changes in their viscosity recommendations to thinner oil, like 10W30.
As far as Nissan service intervals, Nissan is always changing them. When I started with Nissan in 1985, the intervals were 3750 miles (of course, the use of synthetic oil was very rare back in those days compared to now). Then they changed it to 7500 miles, then back to 3750, then back to 7500 and then to 5000 mile intervals. They are also starting to recommend 0W synthetic on some models, but, still say it's okay to use 5W30 conventional voiding the warranty.