LSJR on oil consumption

[OVERKILL]

Quite a few European vehicles where 40 was once recommended, now call for a lower viscosity. Maybe Co2 isn't the only reason.

Conversely, some applications that previously spec'd xW-20 now spec xW-30 (Ford), or spec two different viscosities depending on the usage profile (also Ford). In the OEM space, the pursuit of thinner oils has been primarily about fuel consumption and reducing it, due to government mandates. And this has presented challenges for both the OEM's and the oil licensing bodies which we've discussed the details of in previous threads.

This is different from the racing world where engines aren't expected to last 20 years and lubricant costs aren't a factor, winning is.

This also underscores the problem of quoting bits from a video, that we don't have a summary of, where the content we are expected to engage on, isn't provided for those of us who don't want to watch a video, since the main medium we engage in on this forum is text. This is also why the board rule exists to provide a reasonable summary of any video posted, so people that don't want to watch it, don't have to, while still being able to engage on the content.

 

[scrllock]

The order isn't quite what @DirectRejection said. Fatigued ring tension -> detonation -> even worse ring tension -> loss of oil scraping -> consumption.

Per the video, if ring tension is too low, a higher viscosity oil will cause increased consumption. So presumably the answer is that at least in part, low tension rings have driven viscosity requirements down (though this is certainly in large part due to emissions/fuel economy targets).

 

[Glenda W.]

The question now is has anyone increased oil consumption when increasing grade?

I have not experienced this. Only the opposite.

 

[OVERKILL]

The order isn't quite what @DirectRejection said. Fatigued ring tension -> detonation -> even worse ring tension -> loss of oil scraping -> consumption.

Per the video, if ring tension is too low, a higher viscosity oil will cause increased consumption. So presumably the answer is that at least in part, low tension rings have driven viscosity requirements down (though this is certainly in large part due to emissions/fuel economy targets).

Again, "low tension" rings have been used for decades, with everything up to 60 grade oils. "Low tension" is not a fixed target, but a category with a broad range of coverage.

I'm sure you remember the old "back in the day" bandaide for oil consumption, which was usually the result of stuck, not just weak, oil control rings: heavier oil. You'd slap 20W-50 in that baby and it would drop the consumption down, because the oil control rings weren't able to do their job. What we see here is the argument for the opposite in that scenario, where if the oil rings stop doing their job, either due to poor materials selection or plugging, that the user should go for a thinner oil to reduce that consumption. Have any of us actually seen that work in practice?

Also, there is the fact that oil is heavier when cold, so a car in Winnipeg in January is going to experience much heavier oil in the ring pack area during warm-up than one that's in Dallas in August.

Furthermore, some of these OEM's have simply buggered up ring selection, and it's not due to the fact that they are "low tension", but a combination of tighter ring packs, pushing them up toward the crown, for shorter pistons and less friction, increasing the propensity for varnish, coke and lacquer build-up, coupled with inadequate drainage (I'm looking at you Toyota) and ring material/tension choices that were simply wrong for the application. "Low tension" gets tossed around like a pejorative on here, but it has been properly implemented countless times, so much so that the vast majority of people on here slagging them probably drive a vehicle with them and have no idea, because their design wasn't poorly executed. The HEMI has low tension rings for example, so both my DD's have them.

 

[scrllock]

Again, "low tension" rings have been used for decades, with everything up to 60 grade oils. "Low tension" is not a fixed target, but a category with a broad range of coverage.

I'm sure you remember the old "back in the day" bandaide for oil consumption, which was usually the result of stuck, not just weak, oil control rings: heavier oil. You'd slap 20W-50 in that baby and it would drop the consumption down, because the oil control rings weren't able to do their job. What we see here is the argument for the opposite in that scenario, where if the oil rings stop doing their job, either due to poor materials selection or plugging, that the user should go for a thinner oil to reduce that consumption. Have any of us actually seen that work in practice?

Also, there is the fact that oil is heavier when cold, so a car in Winnipeg in January is going to experience much heavier oil in the ring pack area during warm-up than one that's in Dallas in August.

Furthermore, some of these OEM's have simply buggered up ring selection, and it's not due to the fact that they are "low tension", but a combination of tighter ring packs, pushing them up toward the crown, for shorter pistons and less friction, increasing the propensity for varnish, coke and lacquer build-up, coupled with inadequate drainage (I'm looking at you Toyota) and ring material/tension choices that were simply wrong for the application. "Low tension" gets tossed around like a pejorative on here, but it has been properly implemented countless times, so much so that the vast majority of people on here slagging them probably drive a vehicle with them and have no idea, because their design wasn't poorly executed. The HEMI has low tension rings for example, so both my DD's have them.

Maybe "lower" tension is the correct term then. And to the video's credit, this isn't stated universally--for some engines a decrease OR increase in viscosity will be harmful.

To your point, this is exactly why the Audi EA888.2 had such bad oil consumption. It wasn't that the rings were lower tension, but that they were shorter and positioned differently than the (otherwise identical) VW pistons/rings. People were able to "fix" the problem with EA888.3 rings but they would inevitably revert to oil-burners since the position on the piston itself was the issue.

 

[OVERKILL]

Maybe "lower" tension is the correct term then. And to the video's credit, this isn't stated universally--for some engines a decrease OR increase in viscosity will be harmful.

But have you actually ever heard of this (the latter) happening in practice? That going to thinner oil reduced oil consumption? Because I haven't. That's not to say that it may not happen, but I've never seen evidence.

It would seem to me that if ring tension was so low that the difference in a couple cSt made or broke the engine being an oil burner, that you are going to have oil control issues with cold oil, which is much heavier still and this is guaranteed to be a problem in 10 years when the rings have lost some of their initial tension and experienced wear, because there would be basically no margin for anything. This sounds like something poorly translated from the race car world where engine oil is pre-heated and ring tension can be optimized for a specific viscosity and the engine is getting rebuilt regularly, so longevity isn't a factor either.

To your point, this is exactly why the Audi EA888.2 had such bad oil consumption. It wasn't that the rings were lower tension, but that they were shorter and positioned differently than the (otherwise identical) VW pistons/rings. People were able to "fix" the problem with EA888.3 rings but they would inevitably revert to oil-burners since the position on the piston itself was the issue.

The tension, material, size, placement, these are all design decisions, and they apply to the piston/ring assembly as a whole, not just the rings themselves. You bugger any one of them up and lubricant selection isn't going to fix it, which your Audi example notes. Same goes with the Saturn 1.9L problem and Toyota's buggering this up multiple times.

 

[travis8352]

Didn't realize that was for the Porsche, I thought it was a dexos gen3 mix.

The DI pack he used was dexos 1 gen 3 for the porsche oil

 

[RDY4WAR]

I've run into the low tension situation with a local engine builder. He was complaining that they don't seal and cause a lot of oil consumption. He was using 1/1/2mm ring packs. The problem was he was still putting in the same hone as he did with 1/16" rings which isn't going to work. He was also defaulting to wide bearing clearance (.0035-.0038") which forces a 50 grade oil. The combination of the wrong hone and high viscosity oil was causing the poor seal and oil consumption issues. I gave him some advice and pointed him to some of Lake's videos on rings and hone jobs. He refused to do it that way, with a better hone and tighter clearance, because he was afraid of that "thin as water" oil. He puts a 50 grade in everything. Some people don't care to learn and elevate their game, staying stuck in the past. He still talks trash about thin, low tension rings.

EDIT: This is the same guy who took his wife's Camry to a dealership for a warranty claim because of an engine code pertaining to the variable cam timing. He put Mobil 1 15W-50 in an engine spec'd for 0W-16 and wondered why the VCT wasn't happy. He had a rather loud argument with the techs at the dealership, claiming they want his engine to blow up with that thin oil. The dealership was overly generous by offering to change the oil to the appropriate grade for free. He refused. AFAIK, that Camry is still driving around with a 50 grade oil and check engine light. I'm waiting for the day some actual damage occurs and his warranty gets denied.

 

[OVERKILL]

The DI pack he used was dexos 1 gen 3 for the porsche oil

So the opposite of what I did, where asked Dave to use an A3/B4 A40/LL-01/229.5 additive package for an API application

 

[buster]

Maybe I missed it but why would higher grade oil may not be the best viscosity for low tension piston ring applications?

Shell did a study years ago that demonstrated oil film thickness around the top of the rings was higher with a 20 grade than a 30 grade. Not sure how applicable it is in today's engines.

"Shell Research:
Quote:
The assumption that lower viscosity lubricants automatically give rise to thinner oil films in
key lubricated contacts in a gasoline engine is also open to question, particularly in the case
of piston rings. Laser Induced Fluorescence measurements have found that, in a Nissan
gasoline engine, the mid-stroke top ring oil film thickness was greater for an SAE-5W/20
lubricant than it was for an SAE-15W/40 lubricant. These effects were also observed in our
laboratory for monograde lubricants. Similar effects have been observed by S.L. Moore of
BP36. Figure 20 illustrates the observations. A qualitative explanation of such an effect
could be as follows : There are two routes by which lubricant reaches the top piston ring.
Route #1 (the “conventional” route) is that oil is left on the liner by the passage of the
preceding ring. The higher the oil viscosity, the larger will be the oil film thickness left on
the liner. Route #2 involves oil being transported to the top piston ring via the ring gaps
(such flows have been observed by Nakashima et al37), and this is thought to favour lower
viscosity lubricants. The precise balance between oil transported by the two routes will
determine whether the oil film thickness under the top ring is greater for a lower viscosity
oil or not."

Source:
Improved Fuel Efficiency by Lubricant Design : A Review R.I. Taylor & R.C. Coy Shell Research & Technology Centre, Thornton, P.O. Box 1, Chester, CH1 3SH, UK

 

[OVERKILL]

Shell did a study years ago that demonstrated oil film thickness around the top of the rings was higher with a 20 grade than a 30 grade. Not sure how applicable it is in today's engines.

"Shell Research:
Quote:
The assumption that lower viscosity lubricants automatically give rise to thinner oil films in
key lubricated contacts in a gasoline engine is also open to question, particularly in the case
of piston rings. Laser Induced Fluorescence measurements have found that, in a Nissan
gasoline engine, the mid-stroke top ring oil film thickness was greater for an SAE-5W/20
lubricant than it was for an SAE-15W/40 lubricant. These effects were also observed in our
laboratory for monograde lubricants. Similar effects have been observed by S.L. Moore of
BP36. Figure 20 illustrates the observations. A qualitative explanation of such an effect
could be as follows : There are two routes by which lubricant reaches the top piston ring.
Route #1 (the “conventional” route) is that oil is left on the liner by the passage of the
preceding ring. The higher the oil viscosity, the larger will be the oil film thickness left on
the liner. Route #2 involves oil being transported to the top piston ring via the ring gaps
(such flows have been observed by Nakashima et al37), and this is thought to favour lower
viscosity lubricants. The precise balance between oil transported by the two routes will
determine whether the oil film thickness under the top ring is greater for a lower viscosity
oil or not."

Source:
Improved Fuel Efficiency by Lubricant Design : A Review R.I. Taylor & R.C. Coy Shell Research & Technology Centre, Thornton, P.O. Box 1, Chester, CH1 3SH, UK

Yes, for that application, which they note further down, it's a balance between ring gap and liner adhesion, and this assumes an oil at temperature. You can fine tune these parameters relative to the anticipated viscosity in service, if top ring wear is a problem in testing.

The main focus of the discussion here is the oil control rings, which have the least tension of the group, and how their job is impacted by viscosity selection.

 

[Number_35]

Trigger warning for the Supertech/Kirkland end all and be all oil crowd.

I switched over to SuperTech a few years ago. I feel faint ... I have the vapours ... I must lie down. My delicate constitution can't take it.

 

[buster]

Found this interesting.

https://www.enginebuildermag.com/20...s-inside-viscosity-base-stocks-and-additives/

“Piston rings ride on a thin hydrodynamic oil film that keeps them from contacting the cylinder wall,” says Matthew Bupp of PennGrade. “Without it, the two surfaces could seize, leading to scuffing or ring failure.”

The challenge comes at ring reversal, when the piston changes direction and the oil wave collapses.

“At that point, the film momentarily breaks down,” says Len Groom of AMSOIL. “The ring shifts slightly, and it takes a fraction of a second for that film to rebuild. That’s why you see a wear ridge at the top of the cylinder. In that instant, zinc and phosphorus activate under heat and pressure, creating a sacrificial layer of protection. Now, a synthetic base oil is going to handle that better than a conventional. The natural shear stability, the natural film strength of a synthetic will help during that area of ring reversal.”

 

[ltslimjim]

I've run into the low tension situation with a local engine builder. He was complaining that they don't seal and cause a lot of oil consumption. He was using 1/1/2mm ring packs. The problem was he was still putting in the same hone as he did with 1/16" rings which isn't going to work. He was also defaulting to wide bearing clearance (.0035-.0038") which forces a 50 grade oil. The combination of the wrong hone and high viscosity oil was causing the poor seal and oil consumption issues. I gave him some advice and pointed him to some of Lake's videos on rings and hone jobs. He refused to do it that way, with a better hone and tighter clearance, because he was afraid of that "thin as water" oil. He puts a 50 grade in everything. Some people don't care to learn and elevate their game, staying stuck in the past. He still talks trash about thin, low tension rings.

EDIT: This is the same guy who took his wife's Camry to a dealership for a warranty claim because of an engine code pertaining to the variable cam timing. He put Mobil 1 15W-50 in an engine spec'd for 0W-16 and wondered why the VCT wasn't happy. He had a rather loud argument with the techs at the dealership, claiming they want his engine to blow up with that thin oil. The dealership was overly generous by offering to change the oil to the appropriate grade for free. He refused. AFAIK, that Camry is still driving around with a 50 grade oil and check engine light. I'm waiting for the day some actual damage occurs and his warranty gets denied.

This goes back to understanding things in context. If we don’t know what details combine to reach a more appropriate selection, blindly going as thick as possible could have some drawbacks. Stepping up 4 grades of oil out of fear based narratives is simply, well, based on fears. Overcorrections without enough relevant data to make an informed choice does not necessarily lead to better outcomes. It could simply create a different mode of some other sort of failure.

As @OVERKILL just noted, a racing engine is a different animal. Compare that to a 200k-300k mile family vehicle that’s 15-20 years old…completely different operating conditions for life of equipment.

We see a modest move up a grade or two on this site; typically at most. If consumption were to worsen from this, those individuals would need to regularly track their oil levels during OCIs and create somewhat reliable data; the more the better, regarding any oil usage based on the grade differences.

Maybe most oil consumption; for some, occurs at high loads for longer periods of time? (which Lake brought up to his credit)
Such as driving on the interstate, throttling it to near redline as opposed to the short tripper that doesn’t get up on the throttle hardly at all. Ironically, if the latter always drove that way and didn’t change the oil enough and/or with a less deposit prone oil, it could lead to stuck oil control rings and a different reason for oil consumption. Similar resulting issue, different process and reason for the oil consumption.

 

[buster]

This goes back to understanding things in context. If we don’t know what details combine to reach a more appropriate selection, blindly going as thick as possible could have some drawbacks. Stepping up 4 grades of oil out of fear based narratives is simply, well, based on fears. Overcorrections without enough relevant data to make an informed choice does not necessarily lead to better outcomes. It could simply create a different mode of some other sort of failure.

As @OVERKILL just noted, a racing engine is a different animal. Compare that to a 200k-300k mile family vehicle that’s 15-20 years old…completely different operating conditions for life of equipment.

We see a modest move up a grade or two on this site; typically at most. If consumption were to worsen from this, those individuals would need to regularly track their oil levels during OCIs and create somewhat reliable data; the more the better, regarding any oil usage based on the grade differences.

Maybe most oil consumption; for some, occurs at high loads for longer periods of time? (which Lake brought up to his credit)
Such as driving on the interstate, throttling it to near redline as opposed to the short tripper that doesn’t get up on the throttle hardly at all. Ironically, if the latter always drove that way and didn’t change the oil enough and/or with a less deposit prone oil, it could lead to stuck oil control rings and a different reason for oil consumption. Similar resulting issue, different process and reason for the oil consumption.

In the non-performance passengers cars I've had that is what I've usually noticed.

 

[scrllock]

But have you actually ever heard of this (the latter) happening in practice? That going to thinner oil reduced oil consumption? Because I haven't. That's not to say that it may not happen, but I've never seen evidence.

It would seem to me that if ring tension was so low that the difference in a couple cSt made or broke the engine being an oil burner, that you are going to have oil control issues with cold oil, which is much heavier still and this is guaranteed to be a problem in 10 years when the rings have lost some of their initial tension and experienced wear, because there would be basically no margin for anything. This sounds like something poorly translated from the race car world where engine oil is pre-heated and ring tension can be optimized for a specific viscosity and the engine is getting rebuilt regularly, so longevity isn't a factor either.

Well, yes, but not in the way you mean. I'm sure there are people claiming that they've reduced oil consumption by going from a euro oil to 5w30 R&P, which is thinner but also a totally different product. It would be pretty difficult to control this test, since most brands will have formula variations between their viscosity offerings. I'm sure the R&P crowd will always attribute this to magic chemistry instead of fluid dynamics. Showing that a thinner oil improved oil consumption would be very difficult to do for a consumer.


I'm sure that some of these issues are exacerbated with cold oil, especially short-trippers. Again, many other variables at play but the engines I've personally seem with "bad rings" are also rarely driven more than a few miles at a time.

 

[buster]

Well, yes, but not in the way you mean. I'm sure there are people claiming that they've reduced oil consumption by going from a euro oil to 5w30 R&P, which is thinner but also a totally different product. It would be pretty difficult to control this test, since most brands will have formula variations between their viscosity offerings. I'm sure the R&P crowd will always attribute this to magic chemistry instead of fluid dynamics. Showing that a thinner oil improved oil consumption would be very difficult to do for a consumer.


I'm sure that some of these issues are exacerbated with cold oil, especially short-trippers. Again, many other variables at play but the engines I've personally seem with "bad rings" are also rarely driven more than a few miles at a time.

People often see oil consumption go up towards the end of the interval, which suggests that maybe dirty oil or oil with a certain % of fuel will get consumed faster. Could be a reduction in the piston/ring seal at this point and fuel volatility.

 

[Pablo]

People often see oil consumption go up towards the end of the interval, which suggests that maybe dirty oil or oil with a certain % of fuel will get consumed faster. Could be a reduction in the piston/ring seal at this point and fuel volatility.

I know this happens

Not sure if LSJr addressed it directly but my theory is more oil can escape into the combustion chamber because unclean oil keeps the rings from making an ideal seal.

 

[ChrisD46]

I’ll research video results further after 5 OCI’s of Valvoline Restore and Protect 5W30 in my Hyundai / Kia to see how much (if any) oil consumption has improved ?

 

[buster]

I know this happens

Not sure if LSJr addressed it directly but my theory is more oil can escape into the combustion chamber because unclean oil keeps the rings from making an ideal seal.

Makes a lot of sense to me.