OMG, i had RAV with 3.5L V6 2GR-FE engine for several years and just realized the oil USA toyota tells you to use all the time (5W30 or 0W20 for newer cars) is unsuitable to use during summer while outside USA.
this is thanks to a post by member dkrivosheyev:
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3730861/Re:_0-W20_to_5-W30_swtich#Post3730861
it clearly shows 5W30 is only good up to 10 Celsius and 10W30 or higher is needed above 10C. this russian toyota info is current (MY 2015).
i went ahead and googled some more and found the same info for 2GR-FE from australia toyota (MY2014):
this is thanks to a post by member dkrivosheyev:
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3730861/Re:_0-W20_to_5-W30_swtich#Post3730861
it clearly shows 5W30 is only good up to 10 Celsius and 10W30 or higher is needed above 10C. this russian toyota info is current (MY 2015).
i went ahead and googled some more and found the same info for 2GR-FE from australia toyota (MY2014):