Prius 2017 Engine Oil 0w-16/0w-20

Yes long term. All the taxi cabs that make it to 300-400 k (Gen 4) without significant cylinder wear (according to a professional colleague I know) that run 0w/20 and the newer models (when torn apart) weren't making it as long with the big miles on them running that 16 weight. YMMV of course. I'd stick with 0W-20.

 

What is engine wear?

If there is a film of oil, there is a film of oil. That means no metal to metal wear.
Metal on metal would be a power loss. Maybe that’s what at even 5 k intervals I can hear the engine runs better right after an oil change? I’ve heard this my whole life and that’s getting to be a long time now, like quite a few on here.
If Toyotas use 0w 16 grade oil and get better mpg, how is that a more wear environment if the engine runs with less friction?
My concern with a thinner oil has been it may drain from the engine faster when not being used and cause a drier start in cars like the Prime that sometimes keep the engine off for weeks.

 

Yep there's a long YouTube video posted this weekend where The Car Care Nut (Ahmed) is chatting with David Chao from the Automotive Press. (Both are excellent channels there.)

Anyway, they did talk about how some oil specs changed, yet it's the same engine, like in the Gen 4 Prius. Ahmed said the change was for emission purposes and there's nothing wrong with staying with the original oil viscosity. He did caution folks from deviating too far as it can damage the engine and also effects oil pressures. (Like putting 5W-30 into a car that calls for 0W-20.) I wasn't able to watch the whole thing (about 90 minutes) but a very good watch for any car enthusiasts...talked about recalls and the car industry and upcoming Toyota models and plans. I didn't know this but Toyota (TMC) owns 20% of Subaru and also 5% of Mazda.

They, also, talked about how the EV market has shifted and makers are now going away from them due to poor sales and poor projections for the future.

 

The manual for my 2021 Prime says to use 0w-16. Changing the engine oil is the cheapest maintenance that you can do. Why would you take any shortcut or save a few pennies on a vehicle so valuable? Just saying.

 

This is my thought too. I'd take Toyota's oil recommendations with a grain of salt. Not to dismiss them, but there's likely more factors than engine longevity they're considering.

I'd wager that'd be fine as well.