I am working with a friend who is a great mechanic, but primarily familiar with domestic cars. He refuses to believe the car can run as well as it does and has good compression, adn still have a lower end issue. We started an exploratory tear down in August and found a leaky turbo. It was rebuilt and oil consumption is slightly better but still in the 300 miles / qt. range. His next thought was valve seals or there may be a stuck ring. I have tried 2 doses of engine flush, new oil change, and then used seafoam. I am mid way through the second 3000 mile oil change with seafoam. All appears to be staying the same. I have been typically adding about 8 quarts ( plus the 2 it goes low before I add) over the 3000 miles. There are very minor leaks, but not 8-10 qts worth.

On another site a person actually took apart a bad 3.5L and found the bent rods and the pistons tipped in the cylinder, so a top edge and bottom edge of 2 pistons were worn. This allowed the leakby on the rings. He found his cylinders only very slightly out of round. A thousandth or 2 I think, it might have been 3 or 4.

So I think my next move is head removal and look for tipped pistons. Sixto found this on his 3.5 liter he took the head off, but I don't think he actually took apart the block to see the cause.

Again, any more suggestions or sharing of symptons to help us all understand this would be wonderful.

Chuck