Owned since new. 115K miles. Car manual says 5w20, 10w30 or 5w30. Oil cap says 5w30. Apparently, a TSB came out several years ago saying 5w40 will provide better protection for these turbo engines, which makes sense. For about a year now, I've been using Amsoil SS 5w30 (used M1 5w30 before...