OW-16 vs 0W-20 viscosity specs - does it really matter.

[Direct_Rejection]

Nobody ever discusses temperature in these debates. Even 10° makes a big difference. I think most people would be surprised to know that if a 0w16 vehicle usually is around 200° the oil is thicker at operating temp than another car using 0w20 at 210°.

On my Corolla Cross, the front grill has highly restricted air flow.

Toyota wanted better aerodynamics, and knew coolant/engine temperatures were under control in spite of.

 

[gathermewool]

I was going to post, but…not today, Satan!

 

[4WD]

yes it does, actuator with pwm control varies the volume being pumped to meet a pressure target. No matter how you dress it up, that's what it does.

Variable Displacement: The Future of the Oil Pump is Here – UnderhoodService

Variable displacement oil pumps control how hard the pump works by matching the pressure and volume to engine temperature, loads and engine speeds.

www.underhoodservice.com

As I have posted before - the ECM will sense “demand” - I stomp on it and can see the pressure spike right then even before the RPM ramp up because it just shifted for higher flow …

 

[Jackson_Slugger]

You implied. See here:

Nope. You just read what you want to read...

Since when is GDI an issue? Now, how it's implemented and how each owner takes care of their vehicle, that's a different story. Then again, I've seen carboned up MPI engines that also have fuel dilution issues and their intake valves look disgusting.


Here's a quick example. I'm sure you can find more on your own if you search:

I'm well aware having had one previously., but some models have issues and the industry at large is not good about educating consumers on how they valves need to be cleaned. Fuel dilution can be a problem but probably really shouldn't be....

 

[Jackson_Slugger]

No engine is “designed” to run a grade. An engine can be designed to tolerate thinner grades of oil, but that in no way precludes the use of one that is thicker. Any engine would be destroyed in short order if this were the case.

MOFT protects not harms. The reverse is not true.

I don't disagree completely, but obviously if newer engines are using materials designed to reduce friction and wear, that is no different than any other advancements in engine and lubricant technology since the Model T and I never said using a relatively slight thicker grade will cause any problems. But at the same time, the paranoia of new thinner weights leading to people dumping perfectly good oil in applications specifically recommending them, and this is no different than the 80's and 90's backlash against 5W-30 that predated this message board. It is nice to have such First World quandaries though.....

 

[FZ1]

The oil cap says Nothing.

The manual says 0w-16 recommended, but 0w-20 can be used.

If engine noise is greater with the 16w, I'd think about using the 20w.

 

[BlueOvalFitter]

The oil cap says Nothing.

The manual says 0w-16 recommended, but 0w-20 can be used.

Please don't take this the wrong way, but if the manual reads 0W16 is recommended and 0W20 can be used, why are we into (4) pages of replies? Are you asking for a suggestion on which weight to use, or asking from those that are in the same boat as you and what they use?
Again, no offense.

 

[PimTac]

Please don't take this the wrong way, but if the manual reads 0W16 is recommended and 0W20 can be used, why are we into (4) pages of replies? Are you asking for a suggestion on which weight to use, or asking from those that are in the same boat as you and what they use?
Again, no offense.

It’s neither.

 

[Rod Knock]

Please don't take this the wrong way, but if the manual reads 0W16 is recommended and 0W20 can be used, why are we into (4) pages of replies? Are you asking for a suggestion on which weight to use, or asking from those that are in the same boat as you and what they use?
Again, no offense.

It's probably causing him sleepless nights.

 

[BlueOvalFitter]

It’s neither.

I have read most of the replies and it's all about the oil pump, right? 🤷‍♂️

 

[CR94]

I have read most of the replies and it's all about the oil pump, right? 🤷‍♂️

Oh! I've also read most of the replies, but thought it was just another highly uninformative thick-thin tussle.

 

[ZeeOSix]

Good point. I was looking at the 2023 Prius and it takes 0W-16 as well.

The Toyota OM also says that a thicker oil will give more engine protection in harder use conditions. Guess those Toyota engineers still believe in the science of Tribology. 😃

PS - Why would the Toytota OM say that thicker oil is recommended if the variable output PD pump couldn't still operate with a thicker oil.

 

[ZeeOSix]

I dumped mine and went to 0W-30 and never looked back. I first tried 0W-20 at 400 miles, and the engine ran quieter when idling at operating temperature. I then went to 0W-30 after that, and it ran much quieter. And I dump the filter every oil change. I'll save $5 somewhere else.

I've never had the vehicle back to the dealer since I bought it.

You went TWO grades thicker (0W-16 to 0W-30)? Oh, the horror !!! 😄

 

[ZeeOSix]

yes it does, actuator with pwm control varies the volume being pumped to meet a pressure target. No matter how you dress it up, that's what it does.

Variable Displacement: The Future of the Oil Pump is Here – UnderhoodService

Variable displacement oil pumps control how hard the pump works by matching the pressure and volume to engine temperature, loads and engine speeds.

www.underhoodservice.com

It doesn't say the logic of the control system. I could see the ECU putting the engine into "reduced power mode" when the oil pressure is too low, but why would it do that if the pressure was higher than expected? If the system was so sensitive to oil viscosity, why would all Toyota OMs say you can use a thicker oil for more severe engine use? If the pump system was so sensitive, there should be a big warning statement in the OM to only use a certain oil. They only "recommend" (like ever other vehicle OM), they do not ever say "required" in terms of oil viscosity.

"The wrong oil can set off codes because the ECM knows what the oil pressure should be for a given engine speed and coolant temperature. If the numbers do not match, it will set a code and put the engine into a reduced power mode."

 

[SC Maintenance]

Please don't take this the wrong way, but if the manual reads 0W16 is recommended and 0W20 can be used, why are we into (4) pages of replies? Are you asking for a suggestion on which weight to use, or asking from those that are in the same boat as you and what they use?
Again, no offense.

My question was sort of open ended - primarily because the specs actually overlap - so from a viscosity standpoint a "thick" 16 could really be a "thin" 20. So given that - per the title does it matter? At that point its not even a thick or thin debate because they could in theory be almost the same?

I couldn't find any further comments on the 0w-16 vs 0w-20 viscosity overlap - maybe I don't know how to search. Lots of people say they won't use 0w-16 but given they overlap that lacks logic to me? I am generally in the higher viscosity / HTHS is better camp, but there isn't as much difference as say a 20 vs 30 weight oil?

I didn't want to lead but I was sort of hoping someone would bring up the difference between ILSAC GF6A vs 6B which is only for 0w-16 - and the supposed benefit for LSPI (its not turbo, but its high compression and VVT) and supposed benefit of valve carbon - even though it is dual injected. I haven't seen a lot of real data - just what the SAE says 6B is supposed to do.

I am certainly not loosing any sleep. The engine has 30K on it. I have run both 0w-16 and 0w-20 already, and I run short OCI, so in all practicality it likely doesn't matter. Just trying to get others input on how they think about these things - because that's how I learn, and how I form my own opinion - by logically agreeing or disagreeing with ideas rather than just listen to my own biases?

 

[BlueOvalFitter]

You went TWO grades thicker (0W-16 to 0W-30)? Oh, the horror !!! 😄

My question was sort of open ended - primarily because the specs actually overlap - so from a viscosity standpoint a "thick" 16 could really be a "thin" 20. So given that - per the title does it matter? At that point its not even a thick or thin debate because they could in theory be almost the same?

I couldn't find any further comments on the 0w-16 vs 0w-20 viscosity overlap - maybe I don't know how to search. Lots of people say they won't use 0w-16 but given they overlap that lacks logic to me? I am generally in the higher viscosity / HTHS is better camp, but there isn't as much difference as say a 20 vs 30 weight oil?

I didn't want to lead but I was sort of hoping someone would bring up the difference between ILSAC GF6A vs 6B which is only for 0w-16 - and the supposed benefit for LSPI (its not turbo, but its high compression and VVT) and supposed benefit of valve carbon - even though it is dual injected. I haven't seen a lot of real data - just what the SAE says 6B is supposed to do.

I am certainly not loosing any sleep. The engine has 30K on it. I have run both 0w-16 and 0w-20 already, and I run short OCI, so in all practicality it likely doesn't matter. Just trying to get others input on how they think about these things - because that's how I learn, and how I form my own opinion - by logically agreeing or disagreeing with ideas rather than just listen to my own biases?

If it were my vehicle, I would use a good synthetic 0W20.
My engine (4.2 V6) in my 07 F150 is like a Guinea pig-AKA-test subject, when it comes to which oil I put in it. I have used 0W20, 0W30, 0W40, 5W20, 5W30, and 10W30 in it. It's spec'd 5W20.
When the engine was first built in 1996 it was spec'd 5W30. In the year 2000 Ford spec'd 5w20 and back spec'd 5W20 for the engines made from 1996-1999. It was all about CAFE reasons. The engines tolerances and clearances had never changed from 1996-2008 (2008 was the last year of production). So, I mostly use 5W30 in it.

 

[Jetronic]

It doesn't say the logic of the control system. I could see the ECU putting the engine into "reduced power mode" when the oil pressure is too low, but why would it do that if the pressure was higher than expected? If the system was so sensitive to oil viscosity, why would all Toyota OMs say you can use a thicker oil for more severe engine use? If the pump system was so sensitive, there should be a big warning statement in the OM to only use a certain oil. They only "recommend" (like ever other vehicle OM), they do not ever say "required" in terms of oil viscosity.

"The wrong oil can set off codes because the ECM knows what the oil pressure should be for a given engine speed and coolant temperature. If the numbers do not match, it will set a code and put the engine into a reduced power mode."

Yes but too low oil pressure usually comes from a stuck actuator, meaning the pump is unable to meet it's target pressure. You won't get that with a healthy engine on oil.

 

[Jetronic]

My question was sort of open ended - primarily because the specs actually overlap - so from a viscosity standpoint a "thick" 16 could really be a "thin" 20. So given that - per the title does it matter? At that point its not even a thick or thin debate because they could in theory be almost the same?

I couldn't find any further comments on the 0w-16 vs 0w-20 viscosity overlap - maybe I don't know how to search. Lots of people say they won't use 0w-16 but given they overlap that lacks logic to me? I am generally in the higher viscosity / HTHS is better camp, but there isn't as much difference as say a 20 vs 30 weight oil?

I didn't want to lead but I was sort of hoping someone would bring up the difference between ILSAC GF6A vs 6B which is only for 0w-16 - and the supposed benefit for LSPI (its not turbo, but its high compression and VVT) and supposed benefit of valve carbon - even though it is dual injected. I haven't seen a lot of real data - just what the SAE says 6B is supposed to do.

I am certainly not loosing any sleep. The engine has 30K on it. I have run both 0w-16 and 0w-20 already, and I run short OCI, so in all practicality it likely doesn't matter. Just trying to get others input on how they think about these things - because that's how I learn, and how I form my own opinion - by logically agreeing or disagreeing with ideas rather than just listen to my own biases?

HTHS suitability is a go/no-go thing. You either have enough or you don't. So in that sence, 2.3 vs 2.6 cP can make a world of difference, or no difference at all. What makes it difficult for us to determine if you have enough, is that the actual viscosity in lubrication regimes changes and hths is just 1 data point. Temperature, oil dilution, permanent shear, oxidative thickening, soot loading, all can impact the oil film thickness that HTHS on fresh oil represents.

Kinematic viscosity isn't terribly important, and less of that is peferable in almost every case

 

[ZeeOSix]

HTHS suitability is a go/no-go thing. You either have enough or you don't. So in that sence, 2.3 vs 2.6 cP can make a world of difference, or no difference at all. What makes it difficult for us to determine if you have enough, is that the actual viscosity in lubrication regimes changes and hths is just 1 data point. Temperature, oil dilution, permanent shear, oxidative thickening, soot loading, all can impact the oil film thickness that HTHS on fresh oil represents.

This is why a bit more HTHS headroom above the 2.5 cP baseline is a good thing IMO. There are no real time instruments monitoring all the factors and giving a warning that could impact and cause less engine protection and more wear. Headroom takes care of that without thinking about it, and it's easy to do.

 

[kschachn]

My question was sort of open ended - primarily because the specs actually overlap - so from a viscosity standpoint a "thick" 16 could really be a "thin" 20. So given that - per the title does it matter? At that point its not even a thick or thin debate because they could in theory be almost the same?

I couldn't find any further comments on the 0w-16 vs 0w-20 viscosity overlap - maybe I don't know how to search. Lots of people say they won't use 0w-16 but given they overlap that lacks logic to me? I am generally in the higher viscosity / HTHS is better camp, but there isn't as much difference as say a 20 vs 30 weight oil?

I didn't want to lead but I was sort of hoping someone would bring up the difference between ILSAC GF6A vs 6B which is only for 0w-16 - and the supposed benefit for LSPI (its not turbo, but its high compression and VVT) and supposed benefit of valve carbon - even though it is dual injected. I haven't seen a lot of real data - just what the SAE says 6B is supposed to do.

I am certainly not loosing any sleep. The engine has 30K on it. I have run both 0w-16 and 0w-20 already, and I run short OCI, so in all practicality it likely doesn't matter. Just trying to get others input on how they think about these things - because that's how I learn, and how I form my own opinion - by logically agreeing or disagreeing with ideas rather than just listen to my own biases?

For one thing it's not about viscosity it is about HT/HS. That's the parameter that any license or approval requires. There can be overlap in viscosity and it's not as representative of what happens in the engine as is HT/HS.