[jmatta]

I completely agree it "may" be the use of Mobil 1 (assuming 0W40)...try a heavier weight, as suggested. You are heading into summer there and temps will rise. I've read articles by Jake Raby and Charles Navarro suggesting the rings in the M96 are "loose", contributing to fuel getting past, into the oil; a heavier weight would discourage this. I only drive my '02 in fair weather, use 10W40 high quality synthetic and never need to top off.