Didn't see this topic when I did a search in these forums so I thought I'd post it. I've got a 2012 Honda Accord 2.4 liter 4 cylinder. The factory recommendations are for 0w20 full synthetic oil however I have been told that using 5w20 full synthetic oil meets manufacturer specs and gets better gas mileage. I see that Accord models just a year or two older have basically the same engine but they recommend 5w20 instead. Why did they change the oil from 5w20 to 0w20 and is it safe to use the 5w20 or should I stick with the 0w20? If it matters, I live in KY where the summer temps get up around 100 degrees a few times per year and the winter temps get down around zero a few times per year. Any input is appreciated.