'21 Sienna 2.5l hybrid 202k mi; PU 0w-20 4.6k mi

If you run a 12 centistoke thick 0w30 in this engine, you are unnecessarily stressing it. 0w30 at 150 degrees doesn't sound great. The engine and oil pump would be working hard needlessly.
Not really, it's 10's of thousands of cSt when it's down around -30, engines and oil pumps necessarily are able to handle an extremely wide range of viscosities due to the anticipated operating conditions.

Also, bulk sump temp isn't necessarily reflective of temp in the ring lands or rod bearings.

Deposit "control" is why the opportunity for Valvoline R&P exists.

While saturation of the additive package is visible through sludge and varnish, lacquer-type deposits in the ring belt aren't necessarily directly related to that state, instead, dependent upon a combination of the oil's (and it's constituents) ability to resist turning into deposits when exposed to this environment, and the environment itself. How short is the ring stack, how close is the crown to the rings, how tightly packed are the rings, how much flow through and what type of drainage, as well as flow-through volume in this area.
 
Started the day. Got busy posting here and engine shut off after 190 seconds of idling. It wasn't coming on anways, I had to floor the gas pedal to wake the stupid thing up. After 190 seconds went back to sleep

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Not really, it's 10's of thousands of cSt when it's down around -30, engines and oil pumps necessarily are able to handle an extremely wide range of viscosities due to the anticipated operating conditions.

Also, bulk sump temp isn't necessarily reflective of temp in the ring lands or rod bearings.

Deposit "control" is why the opportunity for Valvoline R&P exists.

While saturation of the additive package is visible through sludge and varnish, lacquer-type deposits in the ring belt aren't necessarily directly related to that state, instead, dependent upon a combination of the oil's (and it's constituents) ability to resist turning into deposits when exposed to this environment, and the environment itself. How short is the ring stack, how close is the crown to the rings, how tightly packed are the rings, how much flow through and what type of drainage, as well as flow-through volume in this area.
Yes but that is for a few minutes until engine gets warm and oil thin. Here I am saying that with such temps on this engine, 0w30 will never get thin, engine will have to deal with very thick oil all day long, all day long.
 
I'm thinking of buying a really premium oil filter that will stay there for 15,000 miles, and I will do five oil changes on it this winter with super tech 0w20. My life will be easy, I won't have to jack up the stupid van in the crappy PNW weather. Fuel dilution will be a lot higher in the winter, Super Tech with 3000 miles will be the best approach
 
engine will have to deal with very thick oil all day long, all day long.
I am confused by this statement. What exactly will the engine need to deal with?

The ECU changes the oil pump rotors effectively changing the pump volume, in a closed loop control such that the oil pressure is going to be the same dependent on conditions no matter what viscosity you run. All you get from thinner oil is more flow, not less stress. Even if it were a conventional pump I don't think the "stress" would be meaningfully different anyway.

So the only question in my mind is the higher flow worth the trade off for giving up a thicker film? So as usual, I understand the engine but not the oil.

Hopefully someone here knows.
 
I am confused by this statement. What exactly will the engine need to deal with?

The ECU changes the oil pump rotors effectively changing the pump volume, in a closed loop control such that the oil pressure is going to be the same dependent on conditions no matter what viscosity you run. All you get from thinner oil is more flow, not less stress. Even if it were a conventional pump I don't think the "stress" would be meaningfully different anyway.

So the only question in my mind is the higher flow worth the trade off for giving up a thicker film? So as usual, I understand the engine but not the oil.

Hopefully someone here knows.
What I understand is that, and I don't know the science and source for it, engines are not designed to operate with cold start like conditions all day long. They want to rapidly get to operating temperature where things get smooth. And you can feel it when a car is fully warmed up. An unnecessarily thick oil will hurt that smoothness. If it is not true than why stop at 0w30? Why not go up further to 5w50? At some point we have to draw a line, and I have drawn that line at 0w20. Some 0w20's, like Mobil 1 Hybrid, are exactly at the highest limit of 0w16. Mobil 1 hybrid 0w20 is 8.2 centistokes where 0w16 ends.
 
What I understand is that, and I don't know the science and source for it, engines are not designed to operate with cold start like conditions all day long. They want to rapidly get to operating temperature where things get smooth. And you can feel it when a car is fully warmed up. An unnecessarily thick oil will hurt that smoothness. If it is not true than why stop at 0w30? Why not go up further to 5w50? At some point we have to draw a line, and I have drawn that line at 0w20. Some 0w20's, like Mobil 1 Hybrid, are exactly at the highest limit of 0w16. Mobil 1 hybrid 0w20 is 8.2 centistokes where 0w16 ends.
If you want the oil to heat up as fast as possible then use a higher grade.

I've never heard that "an unnecessarily thick oil will hurt smoothness", in fact it has always been reported the other way around that a higher HT/HS increases "smoothness" due to a greater film thickness. It's one of the reasons why people tend to report that fresh oil is quieter and smoother.
 
Yes but that is for a few minutes until engine gets warm and oil thin. Here I am saying that with such temps on this engine, 0w30 will never get thin, engine will have to deal with very thick oil all day long, all day long.
The only thing that will be a result of "dealing with it" will be a small increase in fuel consumption. It won't affect the mechanicals in any way, if that's what you mean.

You do realize you're talking about a 30-grade, right? Not a 70-grade.
 
Get yourself an oil extractor. Every thousand miles or so, draw off two quarts and replace with two. Oil dilution % down, TBN up. Only takes a few minutes.
Why not just change oil a bit sooner?

And about the post somewhere on the thread that said changing the thermostat to keep the engine running warmer than 170C. I would recommend not to, because you never know if the engine is designed to run at a particular temperature for the timing, air fuel, etc. Oil is cheap and if fuel dilution is the only concern, just change it sooner or partial change as mentioned, or even use a thicker oil (if you have no time in changing oil). If you want to save money maybe a cheaper 0w20 (SuperTech? Kirkland? I don't know) more often than a higher priced 0w16 with extended / factory OCI.

200k is great, that means what was done is working. The van would last long before the engine wears out due to oil related issue. Save the money and concern for replacement battery in the future instead of the oil.
 
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If you want the oil to heat up as fast as possible then use a higher grade.

I've never heard that "an unnecessarily thick oil will hurt smoothness", in fact it has always been reported the other way around that a higher HT/HS increases "smoothness" due to a greater film thickness. It's one of the reasons why people tend to report that fresh oil is quieter and smoother.
Thank you for the data.

As an aside, do you know why the higher viscosity heats up faster? I am just curios as to the dynamics - I would have guessed the other way around?
 
This thing has a pretty long timing chain. So shear is another entire separate question as well.

Thanks!
Well that would be potential mechanical cleaving of the VII, somewhat different than shear heating in the bearings which would happen even in a no-VII oil.

If I had an engine that was prone to mechanical shear of the VM then I'd be looking at an oil with little or no VII.
 
Yes but that is for a few minutes until engine gets warm and oil thin. Here I am saying that with such temps on this engine, 0w30 will never get thin, engine will have to deal with very thick oil all day long, all day long.
Not really. 0w30 at 70c is still a fraction of the viscosity at 40c or less.

Your engine is fine on 0w20 and 0w16, but it’s also fine on 0w30 and even 0w40. The latter won’t hurt anything but your mpg. Nor are they providing any better wear protection.

Personally if I were in your situation, I’d stick with 0w20 and run it (backed by UOA) until the kv100 fell out of grade on the bottom for sae16 if you want to push ODI with a premium oil. Otherwise I’d just use red jug max life 5w20 on 5k intervals.
 
Have you asked Toyota about it? Has the coolant thermostat been checked or replaced? Is this a normal issue for this model and year of Toyota engines? One thing I know, which won't solve the problem, on big diesel trucks, tractor trailer semi type truck engines, the coolant temp. should run 200 to 212 degrees f, the engine oil temp should run 20 to 30 degrees over your engine coolant temperature. These numbers, at least on a big diesel engines provide maximum engine life, fuel milage, and performance. What is the coolant temperature reading on that same handheld tool you are showing us the engine oil temperature?
 
Have you asked Toyota about it? Has the coolant thermostat been checked or replaced? Is this a normal issue for this model and year of Toyota engines? One thing I know, which won't solve the problem, on big diesel trucks, tractor trailer semi type truck engines, the coolant temp. should run 200 to 212 degrees f, the engine oil temp should run 20 to 30 degrees over your engine coolant temperature. These numbers, at least on a big diesel engines provide maximum engine life, fuel milage, and performance. What is the coolant temperature reading on that same handheld tool you are showing us the engine oil temperature?
Will check the coolant temperature later and report
 
The only thing that will be a result of "dealing with it" will be a small increase in fuel consumption. It won't affect the mechanicals in any way, if that's what you mean.

You do realize you're talking about a 30-grade, right? Not a 70-grade.
That's my point, let's go 70, what's wrong with 70 grade?
 
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