So my 05 G35 6MT has 15K miles on it. I changed the first oil at 500 miles, and every 3500 or so after that using Castrol GTX 10w-30. Use the oem long-can Nissan oil filter.

This sample had a lot of carbon in it - dark colored and smelled "bitter". Made me nervous. My dealer actually did this change (for free, since it was in for other service) and brought it to my attention. They saved a sample, and it's going off to Blackstone today.

I may drive somewhat "spiritedly" ever so often, but haven't ever been to the track - not like it sees a lot of long-term heavy use and redlining. Only use premium fuel from reputable sources.

Ideas or experiences?

 

Sign up at bobistheoilguy.com and read up on "german castrol". This oil seems to be perfect for the VQ. JMO