JARblue

Have you tried the search function? Or use your favorite search engine and add site:the370z.com at the beginning of your search string. All of the questions you're asking have already been asked and answered many times on this forum.

And no one on here can tell you how often you should change your oil any better than your owner's manual can. If you are truly serious about knowing when to change your oil, get a kit from Blackstone and sent in an oil sample for analysis. They will give you recommendations based on actual contaminants in the oil in your car.

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