Can 0w20 handle high RPMs

[tig1]

Originally Posted by ekpolk
Originally Posted by ZeeOSix
Originally Posted by ekpolk
Another poster recently suggested that I go ahead and switch to a 30 wt oil now and start getting better protection... Based upon what???


He's right, based on the many posted up technical papers showing how increased viscosity inreases MOFT and typically the increased HTHS along with it, thereby decreasing wear to a certain degree.

There's a difference between better protection and adequate protection. 20 wt might be adequate for most benignly driven cars (and obviously not adequate in some cases for the benign), but it's not as good at protecting than a thicker oil, even in benign use cases.


No, he's not. You just can't assume that in every application, the engine will, or even can reach the point at which the oil film will compromise. And even if you did, then you'd have to look at how the other components of the oil, in that engine, protect when the film thickness is compromised. You say, "[t]here's a difference between better protection and adequate protection." Are you not assuming that in every case, the engine can and will pass the point of substantially compromised film thickness? How is that a supportable assumption? The computer controlling 1NZ-FXE (the 1.5L from my old Gen-2 Prius) held the maximum rpm to a pretty low 5000 (I have a ScanGauge-II compensating for the car's lack of a tach). The new 18 Prius has the slightly larger 1.8L 2ZR engine, and it appears to be limited to 5500 rpm. Those would hardly seem to be "banshee screaming" high-stress situations that might overstress the oil film. Or that would lead me to ignore what the OM says and substitute the opinions of my friends on BITOG.

And this brings me back to the question I've posed several times, and none of the "thicker is better" advocates have answered: "where are all the vehicles ruined by 20wt oils in the twenty-plus years that car makers have been specifying them?" Again, not the individual special cases, but the overall mass of cars that certainly would have accumulated by now, were the 20s not up to the task. There would be a mixed mass of failures, Accords, Tauruses, Camrys, Civics, all "dying" in mass as they all were damaged over the years by "inferior" 20wt oil. This just hasn't happened.



The thick oil guys are relying on theory not real world evidence. Scientist also support the theory of evolution but real world evidence says otherwise.

 

[PimTac]

This thread reminds me of this oldie.

https://youtu.be/ghj5V5cUo1s

 

[dave1251]

Originally Posted by ZeeOSix
Originally Posted by marc1
Originally Posted by Hootbro
In Australia, the 2GR-FKS (3.5L) Toyota engine in the Highland/Kluger allows anywhere from 0W-20 to 15w40 so long as outside temp considerations are taken in. The 0W-20 and 5W-20 only in the USA market is obviously a CAFE only consideration and not a sole engineering one.

Thanks for this actual info. I have heard people suggest the owner's manual in non-North American sales zones explicitly states alternate viscosity choices but this is the first time I have actually seen it for real and I appreciate it.


There was a thread a while back where all kinds of owner's manual from other countries (no CAFE) of the oil spec pages (for same US models) were posted, looking similar to the above.



Above states 0W20 is recommended at all tempatures thus it's the recommended grade for all situations.

 

[ekpolk]

Originally Posted by Bryanccfshr
To me thin oil is like wearing a seat belt rated for 60mph crashes. It is probably adequate for most traffic accidents. But with your life on the line is adequate for most situations good enough? Or would you prefer a little more protection?

You see how escalating the consequence on a risk matrix makes things become clear?


An interesting analogy, but IMO, it has a critical flaw -- the other end of the scale. Few of us worry about receiving the full protective benefits of our seatbelts in super low speed crashes that happen just as the car gets moving. On the other hand, wear on start-up is different -- can anyone dispute that, under any temperature conditions except near full-temp, 0w-20 is going to flow more freely through the lubrication system upon initial start than 5w30, 10w30 or thicker? I'm not trying to change the subject, but of course, the accumulation of wear occurring upon start-up is also undeniably a factor in engine life, just as is protection at high-speed, high-temp and high load situations.

 

[CR94]

Originally Posted by ekpolk
... can anyone dispute that, under any temperature conditions except near full-temp, 0w-20 is going to flow more freely through the lubrication system upon initial start than 5w30, 10w30 or thicker? ...
Yes, because it isn't (except at extreme low temperatures).

If makes you feel any better, the other extreme in these perennial "T vs. T" arguments often resorts to false logic, too. Reality is somewhere in the middle.

 

[y_p_w]

Originally Posted by ekpolk
And this brings me back to the question I've posed several times, and none of the "thicker is better" advocates have answered: "where are all the vehicles ruined by 20wt oils in the twenty-plus years that car makers have been specifying them?" Again, not the individual special cases, but the overall mass of cars that certainly would have accumulated by now, were the 20s not up to the task. There would be a mixed mass of failures, Accords, Tauruses, Camrys, Civics, all "dying" in mass as they all were damaged over the years by "inferior" 20wt oil. This just hasn't happened.

Sure. There have been cases, but mostly they've been oil sludge cases like the Honda VCM system that would likely have cooked "conventional" 5w30 too. There have been sludge monsters where 5w30 was spec'ed, including Saturns and Toyota 3.0L V6s.

Still - many of the newer cars these days seem to specify 0W-20 motor oil. I was looking at a Honda Civic Type R, which seems to be doing it a different way than the old way Honda did it. Instead of 8000-9000 RPM redlines they're doing it with a turbo and lots of boost. Somehow they're willing to warranty a 306 HP 2.0L turbo 4 for 5 years and 60K miles using 0W-20 and an oil life monitor. Of course that has an oil cooler to help keep the oil temps down.

It may not be the same as doing hot laps around a track, but most warranties won't cover that.

 

[Shannow]

Originally Posted by tig1

With the hundreds of thousands of miles using 0-20, I haven't seen any loss of engine life due to wear. I just don't buy your opinion.


If the engines outlive the car by 100,000 miles, or 50,000 miles, you, the user, won't notice any difference will you ?

It's not "our theory"...it's stated by the OEMs, it's stated by the EPA, and the NHTSA and oil companies what the driver is for the OEMs to go that way...and they offer it while "still offering acceptable engine life" (Honda's words).

If they install a thinner oil (NHTSA state that's the least cost means of improving efficiency - the also state that they must take every reasonable means to ensure that oil is used - hence the manuals), and get a higher CAFE, AND your engine doesn't wear out in your lifetime use - you both win.

However denying that the above is true is asinine...but popular on BITOG.

 

[Shannow]

Originally Posted by ekpolk
On the other hand, wear on start-up is different -- can anyone dispute that, under any temperature conditions except near full-temp, 0w-20 is going to flow more freely through the lubrication system upon initial start than 5w30, 10w30 or thicker? I'm not trying to change the subject, but of course, the accumulation of wear occurring upon start-up is also undeniably a factor in engine life, just as is protection at high-speed, high-temp and high load situations.



Yes, and I can back it up.

Flow does NOT equal lubrication, and at any temperature reasonably above the "W" rating of an oil (lets use freezing as the example), 0W20, or SAE30 will get where it needs to be at about the same time.

 

[Bryanccfshr]

As long as the temperature is warm enough for the oil to be pumped, there is no difference in oil flow speed with a positive displacement pump,if it is 45 degrees outside there is no difference between a 0w40 and a 0w20. In fact they're is no diffenrce in a 15w40 at this temperature for example. Pumping, is pumping, the oil is liquid or it is not. The only advantage of 0w20 at this temp is it takes less energy to pump and for the engine to turn with it in circulation, there is no less wear during warmup with a low viscosity oil when a heavier oil would otherwise pump ( this is excepted for arctic conditions below the pumping viscosity of a heavier oil. But in south central texas I enjoy no additional startup wear protection,. The critical factor in warmup is how long it takes to warmup..
Originally Posted by ekpolk
Originally Posted by Bryanccfshr
To me thin oil is like wearing a seat belt rated for 60mph crashes. It is probably adequate for most traffic accidents. But with your life on the line is adequate for most situations good enough? Or would you prefer a little more protection?

You see how escalating the consequence on a risk matrix makes things become clear?


An interesting analogy, but IMO, it has a critical flaw -- the other end of the scale. Few of us worry about receiving the full protective benefits of our seatbelts in super low speed crashes that happen just as the car gets moving. On the other hand, wear on start-up is different -- can anyone dispute that, under any temperature conditions except near full-temp, 0w-20 is going to flow more freely through the lubrication system upon initial start than 5w30, 10w30 or thicker? I'm not trying to change the subject, but of course, the accumulation of wear occurring upon start-up is also undeniably a factor in engine life, just as is protection at high-speed, high-temp and high load situations.

 

[Shannow]

Originally Posted by tig1
Scientist also support the theory of evolution but real world evidence says otherwise.


Just Wow to prove a point in the thread......so exactly WHAT is your training in engineering and tribology ??

 

[ekpolk]

Originally Posted by CR94
...

If makes you feel any better, the other extreme in these perennial "T vs. T" arguments often resorts to false logic, too. Reality is somewhere in the middle.


It's not about whether I feel good or not. It's all good to me. I'll take this opportunity to emphasize what's down there in my sig block. Note the Avalon. It was originally spec for 5w30, but Toyota has since changed the rec and includes 20wt oils (I forget whether 0w or 5w -- I'm eight hours from where that car is at the moment...). I still use the 30. Why? The engine runs beautifully and it's mileage is going to suck (to me anyway...) no matter what oil we use. In other words, I don't "worship" one oil viscosity or another. I just look at what facts I can find, and try to keep clear the difference between those, and what I might want to believe, for whatever reason.

I strongly doubted the effectiveness of the 20s when they first appeared, 20+ years ago. In the face of the evidence, I've revised my conclusions. I don't doubt that for some particular applications, 20 wt oils are a poor fit. But these particular cases don't establish a general rule. And while some choose to ignore it, the "empty junkyards" argument is awfully hard to get around. Literally, millions and millions of cars and trucks have gone from the manufacturing plant to the junkyard at the end of a long life, and shown no ill effects from being fed 20wt oils.

That does NOT imply that there are absolutely no differences in how an engine wears on a 20 vs a 30, but it does mean that IF there is a difference, and IF it is negative, the effect is so miniscule that it has no impact upon the useful life of the car. Beyond that, the difference is as theoretical as trying to count how many angels can fit on a the head of a pin.

 

[y_p_w]

Originally Posted by ekpolk
That does NOT imply that there are absolutely no differences in how an engine wears on a 20 vs a 30, but it does mean that IF there is a difference, and IF it is negative, the effect is so miniscule that it has no impact upon the useful life of the car. Beyond that, the difference is as theoretical as trying to count how many angels can fit on a the head of a pin.

There are a lot of weird things about the big picture. I believe that in order to meet the Energy Conserving, Resource Conserving, or whatever the heck it's called now, a 5w30 would need to shear down to a lower viscosity during the life of the test in order to meet the requirement. One of the real outliers was when Mobil 1 0W-40 which I understand used to meet the original EC rating by shearing down for the most of the test cycle, but would then thicken to meet the requirement for viscosity loss. Part of the rationale I remember was that 5W-20 may not even be that different over the life of the oil compared to 5w30, except that it's lower viscosity right after an oil change.

But yeah - the question isn't something that can be answered easily given that not only the oil has changed but that the engines have changed. There's just so much that's advanced in manufacturing and materials, as well as the electronics that control engines.

Sure there are extreme cases where the recommendations can practically be tossed. People who race their cars at 10/10ths have a completely different set of requirements than someone who drives a car on the road in a way that doesn't attract cops.

 

[ekpolk]

Originally Posted by Bryanccfshr
As long as the temperature is warm enough for the oil to be pumped, there is no difference in oil flow speed with a positive displacement pump,if it is 45 degrees outside there is no difference between a 0w40 and a 0w20. In fact they're is no diffenrce in a 15w40 at this temperature for example. Pumping, is pumping, the oil is liquid or it is not. . . . .


Then as long as there's oil pressure present, a 20wt would protect will always protect just as well as a 30 or a 40 wt -- because it too is a liquid, just like its thicker relatives. Respectfully (I actually mean that), are you not essentially trying to have it both ways? You're saying that the viscosity is not relevant for pumping purposes (it's a liquid or not), but when it gets to a lubricated clearance between bearings, then it does matter and thicker oils perform "better"? If a given oil's viscosity prevents it from being too easily "squeezed out" of the bearing, then how is viscosity irrelevant as to getting the oil into the bearing?

This discussion is also not accounting for the effect of oil pressure regulation. If the pressure is exceeding the bypass threshold, then in effect, the pump is only "partially" positive displacement, since some of the pumped oil escapes back to the source (sump or tank) as pressure is relieved.

And what about the non-pressure lubricated parts (those receiving their oil by splash, sprayers) and so forth? What goes through a spray nozzle the easiest: water, pancake syrup or molasses? They're all liquids, of course.

All this points to yet another problem that we seldom confront here: there are so many variables at play, at the same time, in our engines, that it is doubtful that it's possible to draw neat, clean conclusions that one vis is "better" than another in cut and dry terms. 20 wt oils are not "better" than 30s, nor is the reverse true. It's the car and engine combo in the particular circumstances where it is used. You think I'm going to put Xw-20 oil into my daughter's 99 Pathfinder that has a zillion miles? Heavens no -- it's already developed a substantial thirst for the conventional High Mileage 10w30 oil that we feed it. Consumption is the dominant issue there, not wear. And on and on...

 

[Shannow]

Originally Posted by ekpolk
Then as long as there's oil pressure present, a 20wt would protect will always protect just as well as a 30 or a 40 wt -- because it too is a liquid, just like its thicker relatives. ...


No, sorry, in that statement, you are displaying an absolute and fundamental misunderstanding of hydrodynamic lubrication.

A thinner oil will always have a thinner Minimum Oil Film Thickness (MOFT) than a thicker oil all things being considered, and be that much closer to asperite contact.

FMs are needed in thinner oils for exactly that aspect, while they may well not be required in thicker oils all else being equal.

Now to the "sprayers", and "pancake" syup...the flow through a short nozzle is related to density and pressure, rather than viscosity....so at operating temperature, the oil with more oil pressure will provide more flow through those orifices...can link you up with my discussions on that in the past.

Pumps being in bypass doesn't matter, as their role is to supply oil to make up for bearing side leakage, the pump isn't to pump oil through the bearings, it's to replenish leakage.

 

[ZeeOSix]

Originally Posted by ekpolk
Originally Posted by ZeeOSix
Originally Posted by ekpolk
Another poster recently suggested that I go ahead and switch to a 30 wt oil now and start getting better protection... Based upon what???

He's right, based on the many posted up technical papers showing how increased viscosity inreases MOFT and typically the increased HTHS along with it, thereby decreasing wear to a certain degree.

There's a difference between better protection and adequate protection. 20 wt might be adequate for most benignly driven cars (and obviously not adequate in some cases for the benign), but it's not as good at protecting than a thicker oil, even in benign use cases.

No, he's not. You just can't assume that in every application, the engine will, or even can reach the point at which the oil film will compromise. And even if you did, then you'd have to look at how the other components of the oil, in that engine, protect when the film thickness is compromised. You say, "[t]here's a difference between better protection and adequate protection." Are you not assuming that in every case, the engine can and will pass the point of substantially compromised film thickness? How is that a supportable assumption? The computer controlling 1NZ-FXE (the 1.5L from my old Gen-2 Prius) held the maximum rpm to a pretty low 5000 (I have a ScanGauge-II compensating for the car's lack of a tach). The new 18 Prius has the slightly larger 1.8L 2ZR engine, and it appears to be limited to 5500 rpm. Those would hardly seem to be "banshee screaming" high-stress situations that might overstress the oil film. Or that would lead me to ignore what the OM says and substitute the opinions of my friends on BITOG.

And this brings me back to the question I've posed several times, and none of the "thicker is better" advocates have answered: "where are all the vehicles ruined by 20wt oils in the twenty-plus years that car makers have been specifying them?" Again, not the individual special cases, but the overall mass of cars that certainly would have accumulated by now, were the 20s not up to the task. There would be a mixed mass of failures, Accords, Tauruses, Camrys, Civics, all "dying" in mass as they all were damaged over the years by "inferior" 20wt oil. This just hasn't happened.

Your all over in the straw field, and missed my main point. If you've absorbed the technical papers often linked in these T vs T discussions, you would see that if holding all things constant, that increasing the viscosity adds protection due to larger MOFT and typically a higher HTHS.

So yes, there is a difference between the level of protection from using oil as thin as possible for reasons driven by CAFE giving "adequate" protection for benignly driven vehicles vs the level given by using a thicker oil. Put 5w30 in those same vehicles and you get some added protection from the increased viscosity factor, regardless if it's "needed" or not. Why do you think the same vehicles sold in other non-CAFE countries show in the oil recommendation specs going all the way up to 40 or 50 wt is acceptable?

 

[ZeeOSix]

Originally Posted by dave1251
Originally Posted by ZeeOSix
Originally Posted by marc1
Originally Posted by Hootbro
In Australia, the 2GR-FKS (3.5L) Toyota engine in the Highland/Kluger allows anywhere from 0W-20 to 15w40 so long as outside temp considerations are taken in. The 0W-20 and 5W-20 only in the USA market is obviously a CAFE only consideration and not a sole engineering one.

Thanks for this actual info. I have heard people suggest the owner's manual in non-North American sales zones explicitly states alternate viscosity choices but this is the first time I have actually seen it for real and I appreciate it.


There was a thread a while back where all kinds of owner's manual from other countries (no CAFE) of the oil spec pages (for same US models) were posted, looking similar to the above.

Above states 0W20 is recommended at all tempatures thus it's the recommended grade for all situations.


The chart and text also says 5w30 is recommended for all temperatures, therefore also for all situations.

 

[Bryanccfshr]

I respectfully will point out as Shanow already has as I slept in my hemisphere that shear and film thickness are different properties than the incompressible nature of liquid and it's behavior in containment.
Liquids pump at the same rate through the pressurized oil circuit to the bearings, nozzles and offices where the oil then does its work. In the bearings the oil is not only being compressed it is being sheared by a rotating shaft, and there is an outlet for oil to escape. The bearing surface is stationary whilethe shaft is moving at a high speed in relation to the bearing surface. It begins removing layers of oil and he oil flows outside the bearing as that is the path of least resistance. HTHS is simply the resistance of oil to be stripped away while being incompressible in this situation.. As long as the oil remains in adequate volume the parts remain separated, if the oil shears too quickly then the quality hydrodynamic lubrication regimen is compromised.
Originally Posted by ekpolk
Originally Posted by Bryanccfshr
As long as the temperature is warm enough for the oil to be pumped, there is no difference in oil flow speed with a positive displacement pump,if it is 45 degrees outside there is no difference between a 0w40 and a 0w20. In fact they're is no diffenrce in a 15w40 at this temperature for example. Pumping, is pumping, the oil is liquid or it is not. . . . .


Then as long as there's oil pressure present, a 20wt would protect will always protect just as well as a 30 or a 40 wt -- because it too is a liquid, just like its thicker relatives. Respectfully (I actually mean that), are you not essentially trying to have it both ways? You're saying that the viscosity is not relevant for pumping purposes (it's a liquid or not), but when it gets to a lubricated clearance between bearings, then it does matter and thicker oils perform "better"? If a given oil's viscosity prevents it from being too easily "squeezed out" of the bearing, then how is viscosity irrelevant as to getting the oil into the bearing?

This discussion is also not accounting for the effect of oil pressure regulation. If the pressure is exceeding the bypass threshold, then in effect, the pump is only "partially" positive displacement, since some of the pumped oil escapes back to the source (sump or tank) as pressure is relieved.

And what about the non-pressure lubricated parts (those receiving their oil by splash, sprayers) and so forth? What goes through a spray nozzle the easiest: water, pancake syrup or molasses? They're all liquids, of course.

All this points to yet another problem that we seldom confront here: there are so many variables at play, at the same time, in our engines, that it is doubtful that it's possible to draw neat, clean conclusions that one vis is "better" than another in cut and dry terms. 20 wt oils are not "better" than 30s, nor is the reverse true. It's the car and engine combo in the particular circumstances where it is used. You think I'm going to put Xw-20 oil into my daughter's 99 Pathfinder that has a zillion miles? Heavens no -- it's already developed a substantial thirst for the conventional High Mileage 10w30 oil that we feed it. Consumption is the dominant issue there, not wear. And on and on...

 

[ka9mnx]

Yep. I really don't care about oil grade but pay close attention to HTHS. w20 HTHS, although proven to be adequate, is bordering on not adequate.

 

[ekpolk]

Originally Posted by Bryanccfshr
I respectfully will point out as Shanow already has as I slept in my hemisphere that shear and film thickness are different properties than the incompressible nature of liquid and it's behavior in containment.
Yes.

Originally Posted by Bryanccfshr
Liquids pump at the same rate through the pressurized oil circuit to the bearings, nozzles and offices where the oil then does its work.
I'm presently half-way through my RE-training as I return to the flying business. Why are we required to keep our engines at low power until until the oil temperature reaches the "green" range on the oil temp gauge? If you put the power much above 1500 rpm while still cold, you can tell with your ears that, while the oil may be forced to the various "nozzles and orifices", it's not moving through them the same as it does when hot. Yesterday morning (~10C, cold for Vero Beach...) I had to pay for 0.2 hours of extra "flight" time pretty much just waiting for the oil temp needle to hit the "green" range. At least it goes in my log book...

Originally Posted by Bryanccfshr
In the bearings the oil is not only being compressed it is being sheared by a rotating shaft, and there is an outlet for oil to escape. The bearing surface is stationary while the shaft is moving at a high speed in relation to the bearing surface. It begins removing layers of oil and he oil flows outside the bearing as that is the path of least resistance. HTHS is simply the resistance of oil to be stripped away while being incompressible in this situation.. As long as the oil remains in adequate volume the parts remain separated, if the oil shears too quickly then the quality hydrodynamic lubrication regimen is compromised.
Right with you on all that. But doesn't this just prove the point that there's much, much more in play than just "thick vs thin," the lone variable of basic viscosity? While there plainly have been exceptions, the evidence shows that, for the vast majority of applications, the 20 wt oils, under normal proper pressure remain in the bearing spaces and resist being sheared sufficiently to protect as intended?

 

[ekpolk]

Originally Posted by ka9mnx
Yep. I really don't care about oil grade but pay close attention to HTHS. w20 HTHS, although proven to be adequate, is bordering on not adequate.


Fair enough, the HTHS numbers of the 20wt oils are almost all, predictably, below those of 30wt oils (2.6-2.7ish vs mid-3s for the 30s seems to be typical), but how do we define adequate or not? Is this not one of the key questions?