hopefully that takes care of the oil consumption. I'll look into the "Subaru" flush thing. Due to living and working in the sticks I haven't heard of that. The 15w40 makes sense, at least you can rule out (or in) mechanical damage. Still fighting the same thing on the Tribeca of Doooom. Luckily for me the buck was passed to the hourly guy. The left bank advance is slow. thinking about a new head for the 3.0L. Possibly you have the same thing has happened to your car. One side is worn more than the other dropping oil pressure on that side, causing reduced cam advance on that side.