It is a weird thing, but Stryfox is correct. When I first got my XF, I took it for the first two oil changes to the dealer. Both times they overfilled it. After that second time around, I bought a TopSider oil pump and pumped out ALL of the oil, measured it and it's EXACTLY 8 quarts. Since then I've done four oil changes myself, 8 quarts each time, and it's perfect...go figure.

BTW - You can get the good fleece filters on e-bay for $15 each (including tax and shipping). With the TopSider, you don't even have to get under the car. It takes about 15 minutes to do oil and filter yourself, and costs about $55 to $60, vs. the $120 the dealer charges to overfill your oil!