This is my first post. I purchased a Ford Explorer this past summer with the 4.6 mod. engine and my concern about the 5W20 oil. Don't worry, I am not going down that road! I am, however putting together a spreadsheet of all the major XW20 and 5W30 oils to compare and contrast to make my selections. I also have a Taurus with the 24V engine. My specific question is this. What top 5 or 6 properties of an oil that would be listed on a PDS would you consider the best criteria for measuring a virgin oil's strength and how would you rank them in importance (ex. [email protected], HTHS, VI etc.). I must admit that I don't fully understand what all the designations mean, but I understand higher is better etc. Thanks! I have been immensely entertained the past few months!