Dirty Synthetic Oil. Change?

Gasket said:

And ensure you always pour that dirty oil down the nearest storm drain so that it can get right back to nature....

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quite true...it's very important that we all recylce. 8)

I use Mobil 1 exclusively in all my engines. This after many years of trials. I change oil once a year. However, none of my engines mileage exceed 7k. I consider this excellent maintenance. Bikes get 4T cars get 0-40 and lawn tractors 15-50...