I was advised by someone who knows about oil to go with Renewable Lube's BIOSYN 10w30. This is the oil that I may go with for my 2.5 4 cyl. Nissan. Has anyone had any success with this motor oil? Has anyone used this motor oil? I am a little leary about using it, but I am willing to try with a little positive feedback. The only information that I can find on here is for the 0w20 and the 5w40. Does anyone have anything on the 5w30 or 10w30?