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WHAT determines WHEN you change it ? ... I do the eyeball, smell and feel-test more than actual mileage.



Go to this YouTube video and fast forward to 1min, 10sec. into the film - http://www.youtube.com/watch?v=BB7PL5MHicU

Case in point, the color of motor oil doesn't determine it's useful life.

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It is funny that people really think that just because they use synthetic oil that they can extend their oil change frequency. The oil whether Dino or synthetic collect the same contaminants and it the contaminants that do the damage not the oil wearing out.



It's equally funny how people think oil filters are created equal just like motor oil. If you want to run an extended life synthetic motor oil, you probably should step up to an extended life oil filter.

Look, I've been driving the point here for a while. The key to determining oil change intervals is with Used Oil Analysis.

I've been doing Used Oil Analysis on my daily driver and can back up what I'm talking about with laboratory analysis.

For example, I went 10-months/7,500-miles on an extended life synthetic motor oil and appropriate oil filter. I then changed the oil and filter, caught a used oil sample and sent it off to an ISO accredited lab for analysis. I even went one step further and paid extra for an ISO particle count to see the larger contaminate particles suspended in the oil. The report I got back stated that the oil was still suitable for use and to re-test after another 3,500-miles or 65-hours. Too bad the oil was already dumped and at the recyclers at that point; money down the drain.

So you have people changing their oil based on color, feel, smell, opinion, but not on the reality of modern oils, filters, and mechanics.