I dunno, never really looked into changing the oil after using such a cleaner.
Not that I'm against changing the oil at all, I go 7500 mi./annually.
But, I would think that there are enough VOCs in these types of cleaners that one good run at speed and operating temp would pretty much purge them from the system.
With an almost 10Qt. Oil System, I don't think there's any real danger. Fuel gets added to the oil all the time and is a very good solvent itself. If these things were much of a factor, I can't believe Porsche would be promoting such a long change interval as they are, or that we don't see even more engines doin' the nasty.
