Both of my hyundai and kia manuals also state that recommendation.@artbuc, the OP, didn't seem to have any concerns about the warranty, as his original question simply asked if there is any other reason to use 0W-16 besides fuel economy. His question implied technical reasons, not warranty related reasons. I find it weird, to say the least, when the Downer Dans pop up in every similar thread and start harping on about warranty. The OP didn't ask that, why bother interjecting?
Now, bellow is page 483 from the Venza Hybrid's owner manual. Please read the highlighted section. What does it say?
Even the manufacturer is concerned about the vehicle being operated on 0W-16 outside of the narrow safety margin of driving it empty, except for passengers, at normal speeds, in a moderate climate, without towing. That right there should be clarification enough about what's right and what's wrong in the eyes of the manufacturer, who by the way, is obligated by the EPA to shove 0W-16 down customer's throats because that is the oil they used to pass the emissions and the fuel economy tests.
View attachment 208096
Simple.....you drive hot and loaded up increase the viscosity.