I switched from Mobil 1 OW-40 to Castrol Syntec (German formula) 0W-30 at about the time I started overfilling. I am leaning towards the oil being the cause, just looking for other people's observations. (BTW, although many people at bobistheoilguy have great data to prove that German Castol is a great oil, if I play with this scenario a bit and the consumption continues I'll be switching back. I might run a UOA on the GC first. Mobil1 UOA's always looked good.)
80k miles on my car now.
But to keep this thread on track and not let it turn into an oil brand debate: Is the 0.5qt overfill connected to increased oil consumption in your experiences? That's the question.
