SAE Paper on Engine Wear with 20 wt. oil

[SubieRubyRoo]

I am still waiting for practical examples where engines with thinner oils wear out faster. Everything else is gray theory that questions the practical relevance

Plenty of “indestructible” Toyotas getting brand new short blocks on Ahmed’s channel. The cherry-picking of data and selective amnesia is almost hilarious.

 

[kschachn]

I am still waiting for practical examples where engines with thinner oils wear out faster. Everything else is gray theory that questions the practical relevance

You truly have no idea what you’re talking about and are just making things up and pulling them out of thin air. And inventing alternate physics along the way.

 

[CarfriendXX]

Volume flow? Here we go again with the alternate physics. The only advantage to thinner oil is slightly increased fuel economy. Nothing else.

And if it were only that, it would still be a gain. Why get fatter when kebab works? As far as I remember, the engines that need thicker oils are also these that are rather broken. I can think of bmw m engines that can't do 100000 even with the thickest w60 oils. Feel free to ask at every taxi station how many Toyotas already have several 100000 miles on it, you will be amazed. If you don't keep up with the times, you go with the times. We also no longer have the 80s in tribology, but apparently some just stop there...

 

[CarfriendXX]

You truly have no idea what you’re talking about and are just making things up and pulling them out of thin air. And inventing alternate physics along the way.

Gerne bleiben sie in den 80er stehen, wo dicke Öle noch „in“ waren. Aber vergessen sie nicht ihr Handy abzugeben 😬😂

 

[CarfriendXX]

Oil pumps with viscosity-dependent capacity are certainly not familiar to them, are they? How an oil volume flow can then be "equal" is a mystery to me. But I think they are smarter than the developers 😬

 

[SubieRubyRoo]

Even in racing, thinner oils are increasingly used

You really don’t understand viscosity and temperature, do you? These engines either have very short runtimes and don’t get fully up to temperature, or have extensive temperature controls and cooling to keep oils cooler than what is seen in daily drivers. Because the oil is colder, it is thicker; they simply shift the viscosity down to compensate for this. If the oils ran 250-300* they would run much thicker oils.

One would think with how much you reference physics, that you’d have even a minimal grasp of the topic. 🤷‍♂️

 

[kschachn]

Oil pumps with viscosity-dependent capacity are certainly not familiar to them, are they? How an oil volume flow can then be "equal" is a mystery to me. But I think they are smarter than the developers 😬

What on earth are you talking about?

More evidence as to your level of understanding in this discussion.

 

[ZeeOSix]

Why should I use thicker oils, more fuel consumption, accept a worse oil volume flow when thinner oils work best? Even in racing, thinner oils are increasingly used, although engines have to last longer without revision than before, funny, isn't it? Gladly fill the thickest oils into the engine to sleep well at night, but they do not speak of "better" in the sense of wear in suitable engines that tolerate thin oils. But that's how it really was, everyone should do what they like.

Do you really understand how an engine oiling system works, and the role the positive displacement oil pump plays? All engine components that are force fed by the PD oil pump will still get the same oil volume supply unless the pump is in pressure relief - just don't rev the engine real high until the oil warms up. Like said many times, if the wrong W rating is used for the use climate it's possible that splashed lubricated components could lack perfect lubrication (but "perfect" lubrication doesn't always equate to lack of lubrication), but you would have to not use the appropriate W rated oil to get into that situation.

Again ... can anyone prove that engines in the cold climates I mentioned earlier are wearing out faster from cold starts when using the right W rated oil than engines in warmer climates? Do people who live in Minnesota, Canada and Alaska have worn out engines at 100K - 150K vs the same vehicles used in Florida? With all this supposed "cold start wear", you'd think that engines way up in the cold northern climates would be junk in short order ... where's that data?

 

[kschachn]

Do you really understand how an engine oiling system works, and the role the positive displacement oil pump plays? All engine components that are force fed by the PD oil pump will still get the same oil volume supply. Like said many times, if the wrong W rating is used for the use climate it's possible that splashed lubricated components could lack perfect lubrication, but you would have to not use the appropriate W rated oil.

Again ... can anyone prove that engines in the cold climates I mentioned earlier are wearing out faster from cold starts when using the right W rated oil than engines in warmer climates? Do people who live in Minnesota, Canada and Alaska have worn out engines at 100K - 150K vs the same vehicles used in Florida? With all this supposed "cold start wear", you'd think that engines way up in the cold northern climates would be junk in short order ... where's that data?

I haven’t seen anything in this thread yet that I believe he understands.

 

[CarfriendXX]

Do you really understand how an engine oiling system works, and the role the positive displacement oil pump plays? All engine components that are force fed by the PD oil pump will still get the same oil volume supply. Like said many times, if the wrong W rating is used for the use climate it's possible that splashed lubricated components could lack perfect lubrication, but you would have to not use the appropriate W rated oil.

Again ... can anyone prove that engines in the cold climates I mentioned earlier are wearing out faster from cold starts when using the right W rated oil than engines in warmer climates? Do people who live in Minnesota, Canada and Alaska have worn out engines at 100K - 150K vs the same vehicles used in Florida? With all this supposed "cold start wear", you'd think that engines way up in the cold northern climates would be junk in short order ... where's that data?

Where do they prove that engines with thin oils wear out earlier? Nothing but grey theory. We end this best, because no one wants to leave their point of view. Should everyone do how and what they want!!

 

[kschachn]

Where do they prove that engines with thin oils wear out earlier? Nothing but grey theory. We end this best, because no one wants to leave their point of view. Should everyone do how and what they want!!

Again, if you showed even a shred of ability to understand and comprehend things that are being given to you, perhaps people may take you more seriously. But as it stands now you’re just trolling this thread with one ridiculous statement after another.

 

[ZeeOSix]

Where do they prove that engines with thin oils wear out earlier? Nothing but grey theory. We end this best, because no one wants to leave their point of view. Should everyone do how and what they want!!

Of course everyone does what they want ... run WD-40 in your engine if you want, nobody really cares what others do.

You're missing the whole point of the discussion. Controlled, detailed engine wear studies all basically conclude that as the oil becomes thinner the wear rate increases. You will never find any other conclusion. So, what people here that like to run a little thicker oil above a xW-20 (which is about the limit on HTHS starting viscosity of 2.5 - 2.6 cP) is that going a bit thicker will add wear protection because of the higher HTHS viscosity, and will ensure more wear protection headroom over the OCI when oil viscosity can be reduced by many factors during use in the engine. It's really not very hard to grasp the logic.

 

[OVERKILL]

And if it were only that, it would still be a gain. Why get fatter when kebab works? As far as I remember, the engines that need thicker oils are also these that are rather broken. I can think of bmw m engines that can't do 100000 even with the thickest w60 oils. Feel free to ask at every taxi station how many Toyotas already have several 100000 miles on it, you will be amazed. If you don't keep up with the times, you go with the times. We also no longer have the 80s in tribology, but apparently some just stop there...

Most performance engines spec heavier oil guy.

Ford spec'd 5W-20 and 5W-50 for the same engine in the same car, the difference being the 5W-50 spec'd vehicle was the "track pack" version that came with an oil cooler and less conservative ECM programming for thermal protection, while the 5W-20 version would get neutered when oil temperature hit a certain point.

Plenty of high mileage S62 bimmer M engines out there, one guy on M5board has something like 400,000 miles on his now, original rod bearings, runs M1 0W-40 in it.

The bigger concern is that you seem to be either oblivious to, or intentionally ignoring the difference between a performance-geared engine and one sold to power an appliance. Let me know the last time someone sustained 300+km/h in a DD'd Corolla.

My Jeep SRT spec's 0W-40 and my wife's truck spec's 5W-20, both engine share the same architecture, but one's marketed and sold with the premise it's going to have the holy hell driven out of it, the other isn't. Same reason GM doesn't spec 0W-20 for the Corvette.

 

[OVERKILL]

Oil pumps with viscosity-dependent capacity are certainly not familiar to them, are they? How an oil volume flow can then be "equal" is a mystery to me. But I think they are smarter than the developers 😬

The vast, VAST majority of oil pumps are positive displacement, do you understand what that means?

 

[ZeeOSix]

We also no longer have the 80s in tribology, but apparently some just stop there...

The physical science of Tribology doesn't really change ... only the formulation of oils and engine designs change.

Yes, it's a fact that as oils become thinner down to 0W-16 and below ,the engines do NEED to have some design changes in order to operate on those thin oils and still last a long time. But many car makers backspeced to xW-20 (to better meet CAFE regulations) when those engines were designed when thicker oils were more common. Ford was a big backspecer to xW-20 ... BUT Ford has lately went back to a 5W-30 for some of the engines they use to spec 5W-20. Why do you think the reason is they would do that? It obviously wasn't to appease CAFE or get better fuel mileage.

 

[ZeeOSix]

Oil pumps with viscosity-dependent capacity are certainly not familiar to them, are they? How an oil volume flow can then be "equal" is a mystery to me. But I think they are smarter than the developers 😬

Even variable volume output positive displacement oil pumps are still moving the same volume regardless of the oil viscosity unless they are in some kind of relief mode - like a fixed PD pump does. I don't think I've seen a variable volume displacement oil pump that controls output volume based on oil pressure or oil viscosity ... just a control system based on engine RPM. Anyone seen anything more sophisticated than that?

 

[Bill_W]

Also....

View attachment 135681 View attachment 135682

Is that from Driven oil website?
Seems clear… Temperature and bearing clearance. I would also add the engine RPM since this is race oil right?

 

[Bill_W]

Even variable volume output positive displacement oil pumps are still moving the same volume regardless of the oil viscosity unless they are in some kind of relief mode - like a fixed PD pump does. I don't think I've seen a variable volume displacement oil pump that controls output volume based on oil pressure or oil viscosity ... just a control system based on engine RPM. Anyone seen anything more sophisticated than that?

You know that the pump pressure relief starts around 2000 RPM and increases from there give or take right?

 

[dnewton3]

We're done here.
The bickering is obscene and the topic has run it's course.
Locked.