Originally Posted By: SirTanon
.. and there is no way I would ever run a 25k OCI, even using Mobil EP. 15k, MAYBE.. using a Fram Ultra.. but never 25k. I don't care what AMSoil says, 25k is too long on any SN/SM oil.
That's a wonderful opinion, But I've seen vehicles go MUCH further than 25,000 miles on Mobil 1 - back in the 1990's.(SG-SH oil?)
There was no such thing as synthetic filters back then. Two vehicles I know of first hand ran over 50,000 with Mobil 1 and the engines seemed to be fine from a cursory examination.
I'm not saying it's a good idea for everyone, but there's probably enough science to suggest that it's possible without causing major problems.