[matt87951]

I've always used Mobil 1 synthetic oil. I run 15W50 in my Porsche, and 10W30 in the Cruiser, I change both at 4k miles. I use either a Mobil 1 filter, or a Purilator Pure One (which in a recent review, has been shown to be the best filter you can buy - Even out proformed K&N) Sorry, I just deleted my bookmark to the review, otherwise I would have put that in here too. But they reviewed if I remember right, about 25 different oil filters, and did a bunch of tests on them.

I agree with quicksilverdon on the acids and contaminants that build up in the oil, which are not filtered out. Which do more harm to the motor then good. I dont know if Mobil 1 is the best oil, but I have never had any touble, and out of all the oils I have used, its been by far the best oil (Quaker State and Pensoil were two of the other I have tried, along with some others over the years)

I think if you wait 25k miles to change your oil, you are just asking to have your motor rebuilt at a very premature age. Just my opinion though.

Matt


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