Everyone is stumped on this. My S80 is having to have almost 2 qts. of oil added before each oil change.
It is not smoking and not puddling. No warnings, etc. Could it be the turbos? Or What? Please, please help us.

 

It is possoble but you would see smoke out of the Tailpipe.

Have a compression test done and a Cylinder leak down test. That will make sure the rings and Valves are good for the most part.