I saw this a while ago, and find it interesting to hear from a REAL engineer talking to a REAL engine builder for one of the major Japanese manufacturers, with his thoughts on oil change intervals, synthetic vs conventional, grades for various seasons, etc.
Many on these forums think the engines are designed for a VERY specific grade/weight, that is not true. The new GH hybrid, with the same 2.5 as the Rav4/Camry/Highlander/Venza hybrids now come with 0w8 as factory fill, and the owners manual has the same B.S. "you can use 0w16 in a pinch but MUST replace with 0w8 at next oil change" verbiage for CAFE reasons, but do you really think Toyota redesigned the ENTIRE engine to only work with a low viscosity oil?
Not going to tell anyone what OCI to use, or whether they should use 0w20 vs 0w16, but for anyone who works on their own vehicles and wants to keep them running well for as long as possible, this is solid information:
