Oil Change every 15k miles?

[clickman]

While I agree, there is this:

http://986forum.com/forums/general-discussions/36191-question%85boxster-s-329-000-miles.html

[Perfectlap]

Originally Posted by clickman

While I agree, there is this:

http://986forum.com/forums/general-discussions/36191-question%85boxster-s-329-000-miles.html

The issue there is that the owner bought his car new back when Mobil 1's formulation was not the same as the formulation you see now. If memory serves, at some point mid-2000's there was change for the worse. Some experts in Excellence Magazine referred to these as "mass market oil that have seen decreasing levels of protective additives". Personally when I see an oil used in Porsches and Mercs being sold cheap at Wal-Mart back when the price of crude was shooting north fast, I have to wonder where they're cutting costs. Which is one reason I like the idea of oil analysis to see for instance how much ZDDP goes in and how much is still present on the way out.

[jdlmodelt]

Originally Posted by Perfectlap

The issue there is that the owner bought his car new back when Mobil 1's formulation was not the same as the formulation you see now. If memory serves, at some point mid-2000's there was change for the worse. Some experts in Excellence Magazine referred to these as "mass market oil that have seen decreasing levels of protective additives". Personally when I see an oil used in Porsches and Mercs being sold cheap at Wal-Mart back when the price of crude was shooting north fast, I have to wonder where they're cutting costs. Which is one reason I like the idea of oil analysis to see for instance how much ZDDP goes in and how much is still present on the way out.

While I don't argue with what you have to say, the guy has run his car for over 300k without the oil analysis and regardless of whether Mobil 1 went inferior when EVERYONE else did just because they sold competitively at Walmart. I'm tempted to go back to 10W40 like my original owner's manual spec'd. Currently, I run 5W50 and 10K miles. I think I'd like to try 10W40 or 15W40. Just because the currently engines are built for 0W40, doesn't mean my old 99 was...