Should I leave a little used oil in? ( DNewton3 )
- Thread starter Linctex
- Start date
- Status
Originally Posted By: Dallas69
Just change the oil and filter man.
You already put 11000 on it and that filter is shot unless its an Ultra.
You worry too much.
PPFT
Pretty much everything above the bottom of barrel (talking to you Frampa) can do 15K...
Just change the oil and filter man.
You already put 11000 on it and that filter is shot unless its an Ultra.
You worry too much.
PPFT
Pretty much everything above the bottom of barrel (talking to you Frampa) can do 15K...
Originally Posted By: tig1
This sounds like changing oil is becoming more complicated all the time. I am not buying none of this. I will just continue to change oil every 10K witch has been my normal for decades.
To be honest, I mostly do my oil and filter separately, because it's quicker and easier for me to do it as two jobs. I'm very busy right now at work and with a family.
So one morning when I have a few spare minutes before work, I jump under the car, no need too jack it up, and swap a cold filter in 2 minutes flat, maybe even less. I can lie on an old rug.
Then another weekend, after shopping or something and when the car is hot, I kick the drain pan under the sump, remove the drain plug, unload the shopping, put the drain plug back in and fill up the oil.
Most of the time my family don't even know I'm doing an oil change, it's so quick. I'm lucky that my car doesn't require jacking up and everything is in easy reach. If I had to jack the car up, then I would probably do oil and filter together, like most of the world.
This sounds like changing oil is becoming more complicated all the time. I am not buying none of this. I will just continue to change oil every 10K witch has been my normal for decades.
To be honest, I mostly do my oil and filter separately, because it's quicker and easier for me to do it as two jobs. I'm very busy right now at work and with a family.
So one morning when I have a few spare minutes before work, I jump under the car, no need too jack it up, and swap a cold filter in 2 minutes flat, maybe even less. I can lie on an old rug.
Then another weekend, after shopping or something and when the car is hot, I kick the drain pan under the sump, remove the drain plug, unload the shopping, put the drain plug back in and fill up the oil.
Most of the time my family don't even know I'm doing an oil change, it's so quick. I'm lucky that my car doesn't require jacking up and everything is in easy reach. If I had to jack the car up, then I would probably do oil and filter together, like most of the world.
Originally Posted By: Linctex
Originally Posted By: chrisri
PSA even published bulletin ...procedure is not followed to the letter, on OC some oil would remain in engine resulting in accelerated (new) oil thickening and engine damage.
Curious.
There's a PDF, sorry can't make link work. Just google:
Oil change procedure on DV6 and DV6U engines.
Originally Posted By: chrisri
PSA even published bulletin ...procedure is not followed to the letter, on OC some oil would remain in engine resulting in accelerated (new) oil thickening and engine damage.
Curious.
There's a PDF, sorry can't make link work. Just google:
Oil change procedure on DV6 and DV6U engines.
Last edited:
Originally Posted By: Linctex
I have read some of DNewton3's posts, and he backs his words up with science. For example:
You'll do yourself a favor if you don't confuse anything dnewton posts with science. Unless reaching conclusions totally unsupported by data has become a scientific field.
I have read some of DNewton3's posts, and he backs his words up with science. For example:
You'll do yourself a favor if you don't confuse anything dnewton posts with science. Unless reaching conclusions totally unsupported by data has become a scientific field.
Originally Posted By: Ducked
This is probably another job for Universal Answer B Man (Nobody Knows) but I'd guess not.
I THINK the used oil (from your refs, and from what I vaguely remember reading) isn't the main thing here, its the established tribofilm. Used oil is mostly relevant because of what isn't in it, and it'll be swamped by the new stuff.
If you're concerned about varnish formation then the only practical way to avoid that is to get most of the oxidised oil out of there.
Or I'm wrong. Could easily be.
More gibrish from the Shell Answer Man. Your last sentence explains it all.
This is probably another job for Universal Answer B Man (Nobody Knows) but I'd guess not.
I THINK the used oil (from your refs, and from what I vaguely remember reading) isn't the main thing here, its the established tribofilm. Used oil is mostly relevant because of what isn't in it, and it'll be swamped by the new stuff.
If you're concerned about varnish formation then the only practical way to avoid that is to get most of the oxidised oil out of there.
Or I'm wrong. Could easily be.
More gibrish from the Shell Answer Man. Your last sentence explains it all.
Last edited:
Originally Posted By: Linctex
I've got 11,000 on some Warren 5W-30 Semi-Syn, and it still "looks" good... (I change a lot of oil in "abused" vehicles - this stuff 'looks like new' compared to some stuff I drain!)
With Texas heat getting hotter and me doing more and more trailer towing, I'm thinking it's time to change the oil.
I have read some of DNewton3's posts, and he backs his words up with science. For example:
Originally Posted By: dnewton3
Additionally, Ford/Conoco proved this as well. Wear rates DROP as the OCI lengthens.
Check out SAE 2007-01-4133; buy it and read it! Ford tested wear at 0 miles, 3k miles, 5k miles, 7.5k miles, 10k miles and even 15k miles; the wear rates were highest upon the OCI and least after 15k miles!
Generally, there is a parabolic curve that is associated with wear rates. The are slightly higher initially, drop down to nearly nothing, and then escalate again after the oil is compromised past its point to deal with contamination.
The "uptick" in wear is due to the tribochemical barrier being removed by the "fresh" detergent package upon installation. Yes - believe it or not, too much of a good thing is a bad thing. Now, DO NOT read too much into this; I'm not saying it will kill any engine. But what I am explaining, and what is abundantly clear in UOA data as well as supported directly with the SAE article, is that the wear is HIGHER upon the initial OCI, because the cleaning additives actually remove the boundary layer that protects the metal parts. Don't believe me? Read the whole article. And review my "normalcy" article as well; there is CLEAR data that shows the wear rates drop the further out you get from an OCI event.
I stand by what I state; it's true despite what rhetoric may contradict it.
Please provide a link to your referenced article; I'd like to read it.
For reference of my claims:
http://papers.sae.org/2007-01-4133/
and my article:
http://www.bobistheoilguy.com/used-oil-analysis-how-to-decide-what-is-normal/
So, I'm thinking of changing the oil to reduce varnish and possible deposit buildup in the engine (not worried about wear too much at all)
My Question:
Should I leave a little used oil in?
1 quart?
2 quarts? (sump & filter holds 6)
It would add "new add pack stuff",
and some new detergents, etc. ...
...but would leaving a little "old" oil help with the "tribochemical barrier" not getting removed?
Change the oil but leave the filter in place. That'll leave some older oil in but you'll have plenty of fresh oil to combat oxidation effects and to reduce the contamination. also, a slightly used filter only gets better.
I've got 11,000 on some Warren 5W-30 Semi-Syn, and it still "looks" good... (I change a lot of oil in "abused" vehicles - this stuff 'looks like new' compared to some stuff I drain!)
With Texas heat getting hotter and me doing more and more trailer towing, I'm thinking it's time to change the oil.
I have read some of DNewton3's posts, and he backs his words up with science. For example:
Originally Posted By: dnewton3
Additionally, Ford/Conoco proved this as well. Wear rates DROP as the OCI lengthens.
Check out SAE 2007-01-4133; buy it and read it! Ford tested wear at 0 miles, 3k miles, 5k miles, 7.5k miles, 10k miles and even 15k miles; the wear rates were highest upon the OCI and least after 15k miles!
Generally, there is a parabolic curve that is associated with wear rates. The are slightly higher initially, drop down to nearly nothing, and then escalate again after the oil is compromised past its point to deal with contamination.
The "uptick" in wear is due to the tribochemical barrier being removed by the "fresh" detergent package upon installation. Yes - believe it or not, too much of a good thing is a bad thing. Now, DO NOT read too much into this; I'm not saying it will kill any engine. But what I am explaining, and what is abundantly clear in UOA data as well as supported directly with the SAE article, is that the wear is HIGHER upon the initial OCI, because the cleaning additives actually remove the boundary layer that protects the metal parts. Don't believe me? Read the whole article. And review my "normalcy" article as well; there is CLEAR data that shows the wear rates drop the further out you get from an OCI event.
I stand by what I state; it's true despite what rhetoric may contradict it.
Please provide a link to your referenced article; I'd like to read it.
For reference of my claims:
http://papers.sae.org/2007-01-4133/
and my article:
http://www.bobistheoilguy.com/used-oil-analysis-how-to-decide-what-is-normal/
So, I'm thinking of changing the oil to reduce varnish and possible deposit buildup in the engine (not worried about wear too much at all)
My Question:
Should I leave a little used oil in?
1 quart?
2 quarts? (sump & filter holds 6)
It would add "new add pack stuff",
and some new detergents, etc. ...
...but would leaving a little "old" oil help with the "tribochemical barrier" not getting removed?
Change the oil but leave the filter in place. That'll leave some older oil in but you'll have plenty of fresh oil to combat oxidation effects and to reduce the contamination. also, a slightly used filter only gets better.
Originally Posted By: chrisri
Originally Posted By: Linctex
Originally Posted By: chrisri
PSA even published bulletin ...procedure is not followed to the letter, on OC some oil would remain in engine resulting in accelerated (new) oil thickening and engine damage.
Curious.
There's a PDF, sorry can't make link work. Just google:
Oil change procedure on DV6 and DV6U engines.
to be honest, That's how it would be done virtually anywhere... While the oil drains I check suspension, brake lines, tyres and pressures, drop the car a bit and inspect/replace brakes. Only after that will I fit the drain plug back and fill with new oil.
Not on my car though, I opt to reduce the oci to +- 10k miles, instead of 22k. But I leave the filter in place, so actually do just over half a change.
Originally Posted By: Linctex
Originally Posted By: chrisri
PSA even published bulletin ...procedure is not followed to the letter, on OC some oil would remain in engine resulting in accelerated (new) oil thickening and engine damage.
Curious.
There's a PDF, sorry can't make link work. Just google:
Oil change procedure on DV6 and DV6U engines.
to be honest, That's how it would be done virtually anywhere... While the oil drains I check suspension, brake lines, tyres and pressures, drop the car a bit and inspect/replace brakes. Only after that will I fit the drain plug back and fill with new oil.
Not on my car though, I opt to reduce the oci to +- 10k miles, instead of 22k. But I leave the filter in place, so actually do just over half a change.
Last edited:
Originally Posted By: CT8
Are we trying to squeeze blood from a Turnip, like a bypass filters,,, who has worn out a properly maintained engine?
Ah hah! Starting in 1962 with a brand new Ford F-100 with 223 ci SIX, 11" clutch and manual granny 4-speed. Pop wore out engine #1 at 157,ooo'ish. I got truck after a wreck to rebuild and use at around 215,ooo'ish. I ran it to just over 300,ooo and that motor was done. #3 went in and the truck ran to 445,ooo and was starting to make crank noises when I sold it.
The issue was not "proper maintenance". It was the center main and that 11" clutch. We always start or stick in neutral with foot off the clutch, but even that OCD process could not save the center main ... With modern cars/trucks that have to be started with clutch depressed, center mains take a beating on cold start. I always wire around the clutch safety switch. But most folks don't ...
The oil for Pop was always Pennz Yellow Can SAE 30 HD. For me it was usually Sta-Lube 30 HD cause it was easy to get on my account. Engine #3 was all Delo 400 15W-40. So the oil did not make a difference with this issue. But, I will say that my compression tests had higher numbers with Sta-Lube, even towards then end of the motor. It was always crank issues that killed it.
No pick-up goes 445,ooo miles without proper maintenance. Original tranny with one drain and refill (Sta-Lube) in all that mileage. Three rear ends because #2 got the housing bent when it dropped in a bad hole with a big load of tools coming out of the mine in the Sierra's. #1 just died at about 200,ooo cause it was worn out (Spicer 44 with posi, all). Original cab, bed and tailgate.
Oils were not the issue - even back then. It was design issues each time.
Are we trying to squeeze blood from a Turnip, like a bypass filters,,, who has worn out a properly maintained engine?
Ah hah! Starting in 1962 with a brand new Ford F-100 with 223 ci SIX, 11" clutch and manual granny 4-speed. Pop wore out engine #1 at 157,ooo'ish. I got truck after a wreck to rebuild and use at around 215,ooo'ish. I ran it to just over 300,ooo and that motor was done. #3 went in and the truck ran to 445,ooo and was starting to make crank noises when I sold it.
The issue was not "proper maintenance". It was the center main and that 11" clutch. We always start or stick in neutral with foot off the clutch, but even that OCD process could not save the center main ... With modern cars/trucks that have to be started with clutch depressed, center mains take a beating on cold start. I always wire around the clutch safety switch. But most folks don't ...
The oil for Pop was always Pennz Yellow Can SAE 30 HD. For me it was usually Sta-Lube 30 HD cause it was easy to get on my account. Engine #3 was all Delo 400 15W-40. So the oil did not make a difference with this issue. But, I will say that my compression tests had higher numbers with Sta-Lube, even towards then end of the motor. It was always crank issues that killed it.
No pick-up goes 445,ooo miles without proper maintenance. Original tranny with one drain and refill (Sta-Lube) in all that mileage. Three rear ends because #2 got the housing bent when it dropped in a bad hole with a big load of tools coming out of the mine in the Sierra's. #1 just died at about 200,ooo cause it was worn out (Spicer 44 with posi, all). Original cab, bed and tailgate.
Oils were not the issue - even back then. It was design issues each time.
it pushes the crank the other way
That 223 Ford was designed about 1953, replaced about 11 years later by the 240 & 300.
Originally Posted By: Lubener
Originally Posted By: Ducked
This is probably another job for Universal Answer B Man (Nobody Knows) but I'd guess not.
I THINK the used oil (from your refs, and from what I vaguely remember reading) isn't the main thing here, its the established tribofilm. Used oil is mostly relevant because of what isn't in it, and it'll be swamped by the new stuff.
If you're concerned about varnish formation then the only practical way to avoid that is to get most of the oxidised oil out of there.
Or I'm wrong. Could easily be.
More gibrish from the Shell Answer Man. Your last sentence explains it all.
Think it explains about half of it, but I did mis-remember the oil-conditioning thing, and shouldn't have posted.
Not so much "gibrish" (assuming you mean gibberish) as just wrong.
Originally Posted By: Ducked
This is probably another job for Universal Answer B Man (Nobody Knows) but I'd guess not.
I THINK the used oil (from your refs, and from what I vaguely remember reading) isn't the main thing here, its the established tribofilm. Used oil is mostly relevant because of what isn't in it, and it'll be swamped by the new stuff.
If you're concerned about varnish formation then the only practical way to avoid that is to get most of the oxidised oil out of there.
Or I'm wrong. Could easily be.
More gibrish from the Shell Answer Man. Your last sentence explains it all.
Think it explains about half of it, but I did mis-remember the oil-conditioning thing, and shouldn't have posted.
Not so much "gibrish" (assuming you mean gibberish) as just wrong.
Last edited:
dnewton3
Staff member
Originally Posted By: Shannow
That paper keeps getting trotted out as proof of something that the paper never tested nor demonstrated.
They took a bunch of used oils, some of which were utterly shagged, had thickened excessivly and had poor TBN.
Then they use a contacting surface tribometer and measured the establishment of the tribofilms with new and progressively used oil. The used oil formed tribofilms on fresh metal surfaces quicker than fresh.
This is entirely to be expected, as the first part of the laying down of tribofilms involves partial destruction of the ZDDP/Mo into more reactive species...some additive companies put a lot of different elemental "variaties" in so that there are different points of activation.
So the oil with the most already partially reacted species in it produced the best tribofilms the earliest...exactly as expected.
The Used oil, excessively thick, wiht no TBN to speak of was not necessarily the best oil to have in the engine. Extrapolating the limits (surface tribometer) of this study INTO that realm is really stretching the bow a bit (well a lot).
And at OCI, the quote that you have provided assumes that ALL of the tribofilm is removed to fresh metal (not true, never seen anything on that).
As to the thought process...
https://bobistheoilguy.com/forums/ubbthreads.php/topics/4060600/1
Your observations, and subsequent concerns, are misplaced, as we've talked before.
I'll address your contentions by concept.
First, the talk about how "shagged" (used up) these oils are due to the vis thickening and the TBN/TAN crossover. As I pointed out in other posts, these are essentially meaningless. You keep bringing them up as if they have merit, but they do not. I'll yet again quote the SAE study referenced:
"It is interesting to note the viscosity of the 7500 mile drain oil is about 20% higher (at 100c) than that of the 3000 mile drain oil and therefore, might be expected to show a lower wear rate because of increased oil film and the resulting reduction in asperity contact. But both oils showed similar wear rates indicating that the wear rate is controlled more by the chemistry of the surface film at the contact than asperity contacts."
You see, despite the thickening and TAN rise, the wear rates did not change;; they stayed essentially the same. Hence, you cannot claim that these two issues (vis and acid) have any merit if they had no effect on the outcome. If there is no correlation (if one characteristic changes, but another does not) then you CANNOT claim there is causation (something affected another attribute). No change in the wear rates means that vis and acid had no affect despite their presence. How you cannot understand this is beyond me; it is CLEARLY explained and denoted in the conclusions of the SAE study.
Also, it is important to understand that the study I reference (2007-01-4133) incorporates information from other SAE studies (which is a very common practice). This study credits info from Fujita et all, which demonstrates that "the lube-derived film increases steadily with test duration and then stabilizes at the 50-100nm level. This thickness is almost independent of the phosphorous concentration". It went on the show that "Film thickness is also dependent on oil temperature with higher temperatures tending to promote greater film thickness. However, when a dispersant is added, the film is removed ..." Other studies referenced in 2007-01-4133 speak to the types of ZDDP that have been studied, and how other detergents and dispersants alter the film barrier being discussed. The study further explains that "They observed that the wear reducing capacility changed with the oil aging and the ZDDP decompsition products gave even better wear reducing capability and lower friction than the ZDDP itself". IOW - the film barrier (TCB) is essentially a byproduct of the ZDDP degradation, but that TCB is actually more important in reducing wear than the ZDDP itself! And it's not just this study (2007-01-4133); it's the culmination of several studies that come to this conclusion. The oils used in the 2007-01-4133 study (which you call a "bunch", but were actually only three) were clearly described in the study. They were:
1) a GF3 with phos at .10%
2) a GF4 with phos at .08%
3) a GF4 with phos at .05%
And yet, despite the difference in phos levels, the wear rate trends were nearly identical. What does this prove? That there is not a direct relationship between phos and wear. While there may be an INdirect relationship, in that the ZDDP is used as a necessary contributor to TCB, the phos levels in this study, in and of themselves, do not alter the wear rates. What alters the wear rates? OCI duration relative to TCB thickness.
Further, regarding the topic of the SAE study using oils to measure film barriers ...
Yes they took used oil and tested it in some lab rigs; how else would they be able to so accurately track the TBC thickness? So what? If I understand your objection correctly, it's that they used oils with varying amount of accumulated duration (different mileage) and then tested them; obviously showing the "older" oils developed the TBC sooner. I get that, and I don't object to that. But what you seem to want to ignore is that real world data (a huge truckload of data; over 15,000 UOAs) shows similar results. In all my UOA data, folks are not swapping their oils out to alter or manipulate the TCB; they run the oil from fresh-change to some predetermined limit. Some folks OCI often; others run the lubes way out. But the data shows that as the OCI is extended, the wear rates drop to very low rates.
In short, multiple SAE studies (not just one) have shown how the TCB is established, and how it goes unaffected by other inputs. Further, it is proven that "fresh" oils degrade the TCB, and that heat/oxidation/duration improve the TCB. They show that the ZDDP has less effect on wear rates, than the TCB film it promotes. All these studies are credited in 2007-01-4133; they are listed in the reference section. Are you saying that all these studies are misleading; that none of them prove what is claimed? There are 22 referenced sources; they are all wrong and you're right?
My data echos the conclusions of the multiple SAE studies, but from a different perspective. Whereas the SAE studies take a very scientific perspective, measuring the actual TCB thickness and showing HOW the TCB is developed, my data shows the EFFECTS of that TCB, relative to the OCI duration. The Ford/Conoco study showed in a lab as to how more mature oils develop a thicker barrier. My study showed that real world field trials (15k UOAs) come to the same conclusion. It's the best of both worlds; when SAE studies are backed up by real experiences, it's hard to deny their relevance. It is the combination of the information of the SAE studies, along with the reams of data I have, that leads to a VERY REAL AND LOGICAL CONCLUSION that the TCB, once established, reduces wear to very low levels. And that other inputs (such as vis, acids, etc) don't have a major effect on wear.
You have stated that oil is "shagged" and "completely totaled" because the vis got thicker and the acid flipped. So what? Show me that it matters, sir. What study data do you know of, what can you point towards, that indicates the shift in inputs has any affect on the output (wear rates)? All the information we have available (multiple SAE studies and mounds of UOA data) show that despite the oils experiencing attribute changes (vis shift and acid flip), the wear rates remained steady.
It boils down to this; the SAE studies have shown that the TCB is first removed by fresh detergents/dispersants. After than stripping, heat/time cause the re-formation of the TCB. That TCB will stabilize between 50-100nm of thickness. Once TCB is established, the wear rates go to "near-zero" and become very stable. At some point, it is reasonable to believe that the contamination loading of the sump would overcome this TCB benefit; that particulate would overcome the TCB effect. And while we do not know when that would start, we know from more than 15,000 UOAs that it is AT LEAST past 15k miles, because my data shows this phenomenon with ultra-clear facts. My data shows that wear rates drop around 3k miles, and continue to be very low out to 15k miles. In all manner of engines; gas and diesel, large and small, air and liquid cooled, carb'd and fuel injected, "severe" or not ...
Your objections are noted, and summarily dismissed.
That paper keeps getting trotted out as proof of something that the paper never tested nor demonstrated.
They took a bunch of used oils, some of which were utterly shagged, had thickened excessivly and had poor TBN.
Then they use a contacting surface tribometer and measured the establishment of the tribofilms with new and progressively used oil. The used oil formed tribofilms on fresh metal surfaces quicker than fresh.
This is entirely to be expected, as the first part of the laying down of tribofilms involves partial destruction of the ZDDP/Mo into more reactive species...some additive companies put a lot of different elemental "variaties" in so that there are different points of activation.
So the oil with the most already partially reacted species in it produced the best tribofilms the earliest...exactly as expected.
The Used oil, excessively thick, wiht no TBN to speak of was not necessarily the best oil to have in the engine. Extrapolating the limits (surface tribometer) of this study INTO that realm is really stretching the bow a bit (well a lot).
And at OCI, the quote that you have provided assumes that ALL of the tribofilm is removed to fresh metal (not true, never seen anything on that).
As to the thought process...
https://bobistheoilguy.com/forums/ubbthreads.php/topics/4060600/1
Your observations, and subsequent concerns, are misplaced, as we've talked before.
I'll address your contentions by concept.
First, the talk about how "shagged" (used up) these oils are due to the vis thickening and the TBN/TAN crossover. As I pointed out in other posts, these are essentially meaningless. You keep bringing them up as if they have merit, but they do not. I'll yet again quote the SAE study referenced:
"It is interesting to note the viscosity of the 7500 mile drain oil is about 20% higher (at 100c) than that of the 3000 mile drain oil and therefore, might be expected to show a lower wear rate because of increased oil film and the resulting reduction in asperity contact. But both oils showed similar wear rates indicating that the wear rate is controlled more by the chemistry of the surface film at the contact than asperity contacts."
You see, despite the thickening and TAN rise, the wear rates did not change;; they stayed essentially the same. Hence, you cannot claim that these two issues (vis and acid) have any merit if they had no effect on the outcome. If there is no correlation (if one characteristic changes, but another does not) then you CANNOT claim there is causation (something affected another attribute). No change in the wear rates means that vis and acid had no affect despite their presence. How you cannot understand this is beyond me; it is CLEARLY explained and denoted in the conclusions of the SAE study.
Also, it is important to understand that the study I reference (2007-01-4133) incorporates information from other SAE studies (which is a very common practice). This study credits info from Fujita et all, which demonstrates that "the lube-derived film increases steadily with test duration and then stabilizes at the 50-100nm level. This thickness is almost independent of the phosphorous concentration". It went on the show that "Film thickness is also dependent on oil temperature with higher temperatures tending to promote greater film thickness. However, when a dispersant is added, the film is removed ..." Other studies referenced in 2007-01-4133 speak to the types of ZDDP that have been studied, and how other detergents and dispersants alter the film barrier being discussed. The study further explains that "They observed that the wear reducing capacility changed with the oil aging and the ZDDP decompsition products gave even better wear reducing capability and lower friction than the ZDDP itself". IOW - the film barrier (TCB) is essentially a byproduct of the ZDDP degradation, but that TCB is actually more important in reducing wear than the ZDDP itself! And it's not just this study (2007-01-4133); it's the culmination of several studies that come to this conclusion. The oils used in the 2007-01-4133 study (which you call a "bunch", but were actually only three) were clearly described in the study. They were:
1) a GF3 with phos at .10%
2) a GF4 with phos at .08%
3) a GF4 with phos at .05%
And yet, despite the difference in phos levels, the wear rate trends were nearly identical. What does this prove? That there is not a direct relationship between phos and wear. While there may be an INdirect relationship, in that the ZDDP is used as a necessary contributor to TCB, the phos levels in this study, in and of themselves, do not alter the wear rates. What alters the wear rates? OCI duration relative to TCB thickness.
Further, regarding the topic of the SAE study using oils to measure film barriers ...
Yes they took used oil and tested it in some lab rigs; how else would they be able to so accurately track the TBC thickness? So what? If I understand your objection correctly, it's that they used oils with varying amount of accumulated duration (different mileage) and then tested them; obviously showing the "older" oils developed the TBC sooner. I get that, and I don't object to that. But what you seem to want to ignore is that real world data (a huge truckload of data; over 15,000 UOAs) shows similar results. In all my UOA data, folks are not swapping their oils out to alter or manipulate the TCB; they run the oil from fresh-change to some predetermined limit. Some folks OCI often; others run the lubes way out. But the data shows that as the OCI is extended, the wear rates drop to very low rates.
In short, multiple SAE studies (not just one) have shown how the TCB is established, and how it goes unaffected by other inputs. Further, it is proven that "fresh" oils degrade the TCB, and that heat/oxidation/duration improve the TCB. They show that the ZDDP has less effect on wear rates, than the TCB film it promotes. All these studies are credited in 2007-01-4133; they are listed in the reference section. Are you saying that all these studies are misleading; that none of them prove what is claimed? There are 22 referenced sources; they are all wrong and you're right?
My data echos the conclusions of the multiple SAE studies, but from a different perspective. Whereas the SAE studies take a very scientific perspective, measuring the actual TCB thickness and showing HOW the TCB is developed, my data shows the EFFECTS of that TCB, relative to the OCI duration. The Ford/Conoco study showed in a lab as to how more mature oils develop a thicker barrier. My study showed that real world field trials (15k UOAs) come to the same conclusion. It's the best of both worlds; when SAE studies are backed up by real experiences, it's hard to deny their relevance. It is the combination of the information of the SAE studies, along with the reams of data I have, that leads to a VERY REAL AND LOGICAL CONCLUSION that the TCB, once established, reduces wear to very low levels. And that other inputs (such as vis, acids, etc) don't have a major effect on wear.
You have stated that oil is "shagged" and "completely totaled" because the vis got thicker and the acid flipped. So what? Show me that it matters, sir. What study data do you know of, what can you point towards, that indicates the shift in inputs has any affect on the output (wear rates)? All the information we have available (multiple SAE studies and mounds of UOA data) show that despite the oils experiencing attribute changes (vis shift and acid flip), the wear rates remained steady.
It boils down to this; the SAE studies have shown that the TCB is first removed by fresh detergents/dispersants. After than stripping, heat/time cause the re-formation of the TCB. That TCB will stabilize between 50-100nm of thickness. Once TCB is established, the wear rates go to "near-zero" and become very stable. At some point, it is reasonable to believe that the contamination loading of the sump would overcome this TCB benefit; that particulate would overcome the TCB effect. And while we do not know when that would start, we know from more than 15,000 UOAs that it is AT LEAST past 15k miles, because my data shows this phenomenon with ultra-clear facts. My data shows that wear rates drop around 3k miles, and continue to be very low out to 15k miles. In all manner of engines; gas and diesel, large and small, air and liquid cooled, carb'd and fuel injected, "severe" or not ...
Your objections are noted, and summarily dismissed.
dnewton3
Staff member
To the OP -
No, don't leave in some portion of used oil. Either leave it all in there, or change it.
OCIs do NOT induce a death-march of engine wear. Fresh oil does degrade the TCB; that's proven. But it's not harmful by any means.
My data, and the SAE studies, show that longer OCIs are very safe in terms of wear rates. But do NOT take an approach as to assume that if one direction is safe, the other is unsafe; that is untrue.
The concepts to glean are this:
- longer OCIs are safe; the wear rates are very low out to 15k miles
- shorter OCIs do not benefit with lower wear rates; they exhibit a higher wear rate (although not an unsafe one)
Folks that OCI frequently seem to believe that is something is good, more must be better. Changing oil more often, is neither helpful nor hurtful. Unless you count the pain in your wallet from throwing away perfectly functional fluids.
If you're going to OCI, then do so. Don't "partial it". If not, leave it alone.
If you'll Hades-bent on some experiment, then go for it! But track your data; oil used, oil dumped, UOAs, etc.
It would be my prediction that you'll not be able to discern much when viewed from macro data analysis. The everyday variables will overshadow your perceived results.
No, don't leave in some portion of used oil. Either leave it all in there, or change it.
OCIs do NOT induce a death-march of engine wear. Fresh oil does degrade the TCB; that's proven. But it's not harmful by any means.
My data, and the SAE studies, show that longer OCIs are very safe in terms of wear rates. But do NOT take an approach as to assume that if one direction is safe, the other is unsafe; that is untrue.
The concepts to glean are this:
- longer OCIs are safe; the wear rates are very low out to 15k miles
- shorter OCIs do not benefit with lower wear rates; they exhibit a higher wear rate (although not an unsafe one)
Folks that OCI frequently seem to believe that is something is good, more must be better. Changing oil more often, is neither helpful nor hurtful. Unless you count the pain in your wallet from throwing away perfectly functional fluids.
If you're going to OCI, then do so. Don't "partial it". If not, leave it alone.
If you'll Hades-bent on some experiment, then go for it! But track your data; oil used, oil dumped, UOAs, etc.
It would be my prediction that you'll not be able to discern much when viewed from macro data analysis. The everyday variables will overshadow your perceived results.
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Originally Posted By: dnewton3
They show that the ZDDP has less effect on wear rates, than the TCB film it promotes. All these studies are credited in 2007-01-4133; they are listed in the reference section. Are you saying that all these studies are misleading; that none of them prove what is claimed? There are 22 referenced sources; they are all wrong and you're right?
Logical fallacy...you are strawmanning me there...
So...point out where I've stated that...you can directly quote me if you want where I am saying those papers are wrong.
You can include links to where I've included various papers on the development of tribofilms with additive "activation" (partial breakdown) including the breakdown of moly compounds to MoS2, in the ZnFe phospate "glass" if you want for completeness.
They show that the ZDDP has less effect on wear rates, than the TCB film it promotes. All these studies are credited in 2007-01-4133; they are listed in the reference section. Are you saying that all these studies are misleading; that none of them prove what is claimed? There are 22 referenced sources; they are all wrong and you're right?
Logical fallacy...you are strawmanning me there...
So...point out where I've stated that...you can directly quote me if you want where I am saying those papers are wrong.
You can include links to where I've included various papers on the development of tribofilms with additive "activation" (partial breakdown) including the breakdown of moly compounds to MoS2, in the ZnFe phospate "glass" if you want for completeness.
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What about fuel efficiency? Does fuel consumption rise as an engine oil ages, improve or stay the same? I would not be saving money if added cost of fuel was higher than the cost of a few liters of oil. Also, do oil filters trap smaller particles as they age in service? How many miles before an oil filter becomes plugged and no linger filters? How much information can be obtained from a UOA? For example 10 liters of oil with 30 ppm of iron is how many grams? How many grams of iron would need to be removed from an engine before it would be considered worn out? I guess that would depend on the size of the engine. As engines wear, the rate of wear would also change over miles, hours and load, and not just one or the other.
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dnewton, I would appreciate a look at the papers that demonstrate that the tribofilm is completely removed at oil change. I've never come across anything that demonstrates that you go back to virgin metal with an oil change, but am happy to be educated.
Please provide the numbers...I'll buy them myself.
Please provide the numbers...I'll buy them myself.
Originally Posted By: userfriendly
What about fuel efficiency? Does fuel consumption rise as an engine oil ages, improve or stay the same? I would not be saving money if added cost of fuel was higher than the cost of a few liters of oil. Also, do oil filters trap smaller particles as they age in service? How many miles before an oil filter becomes plugged and no linger filters? How much information can be obtained from a UOA? For example 10 liters of oil with 30 ppm of iron is how many grams? How many grams of iron would need to be removed from an engine before it would be considered worn out? I guess that would depend on the size of the engine. As engines wear, the rate of wear would also change over miles, hours and load, and not just one or the other.
Fuel consumption evolves, but can go either way or even both ways: ie better aftera few k miles, and starting to worsen again a few k later... In the end, all oils will cause higher fuel consumption as they thicken from oxidation or contaminant loading.
Fuel filters with some use on them catch more and smakller particles. There's a member on here who regularly sampled his oil and had particle counts performed while keeping the same filter. For his application, particle counts dropped every time (at first only the bigger particles, then the smaller aswell) until about 44k miles when all particles saw a sudden rise again. So for him it seems 40k was a good time to change the filter. At 44k he was back at the particle count of the first oci. But this will be different for every car and filter and oil.
You can't get anything worthwile out of the 30ppm of iron with regards to wear: oxidation also strips iron from the block but this doesn't have to be in any location where the wear actually matter, this can be from the sides of the block aswell. Same goes for aluminium.
What about fuel efficiency? Does fuel consumption rise as an engine oil ages, improve or stay the same? I would not be saving money if added cost of fuel was higher than the cost of a few liters of oil. Also, do oil filters trap smaller particles as they age in service? How many miles before an oil filter becomes plugged and no linger filters? How much information can be obtained from a UOA? For example 10 liters of oil with 30 ppm of iron is how many grams? How many grams of iron would need to be removed from an engine before it would be considered worn out? I guess that would depend on the size of the engine. As engines wear, the rate of wear would also change over miles, hours and load, and not just one or the other.
Fuel consumption evolves, but can go either way or even both ways: ie better aftera few k miles, and starting to worsen again a few k later... In the end, all oils will cause higher fuel consumption as they thicken from oxidation or contaminant loading.
Fuel filters with some use on them catch more and smakller particles. There's a member on here who regularly sampled his oil and had particle counts performed while keeping the same filter. For his application, particle counts dropped every time (at first only the bigger particles, then the smaller aswell) until about 44k miles when all particles saw a sudden rise again. So for him it seems 40k was a good time to change the filter. At 44k he was back at the particle count of the first oci. But this will be different for every car and filter and oil.
You can't get anything worthwile out of the 30ppm of iron with regards to wear: oxidation also strips iron from the block but this doesn't have to be in any location where the wear actually matter, this can be from the sides of the block aswell. Same goes for aluminium.
dnewton3
Staff member
Originally Posted By: Shannow
dnewton, I would appreciate a look at the papers that demonstrate that the tribofilm is completely removed at oil change. I've never come across anything that demonstrates that you go back to virgin metal with an oil change, but am happy to be educated.
Please provide the numbers...I'll buy them myself.
I don't know that I ever stated the TCB is completely removed. I have said, and the study concludes, that the TCB is reduced significantly by a fresh load of oil. But neither I nor the study ever said it was completely gone. I have used the term "remove" (as do they in the studies) in a general sense; if you took it to mean completely and utterly devoid then I've given the wrong impression. It is not reduced back to "virgin metal"; it (the TCB) is significantly reduced.
From Page 7 ...
"Is is likely that the film will be removed ultimately or replaced by a different type of film, but it points to the fact that once the film is formed with a fully formulated oil, it is not removed very quickly. The existing film may affect the chemical mechanism for forming the new film which provided the reduced friction and wear rate benefit."
Further, the other studies incorporated by reference clearly describe that different formulation of ZDDP, reacting with different formulations of oil lube packages, will make for different rates at which the TCB will decay at an OCI, and rate at which it will form a new "skin" (layer, whatever you want to call it).
From page 3 ...
Film thickness is also dependent on oil temperature with higher temperatures tending to promote greater film thickness. However, when a dispersant is added, the film is removed and the film thickness stabilizes at a lower value. The antagonistic behavior of dispersants is well-known and one of the possible mechanisms was believed to be the competition between dispersant and ZDDP molecules to absorb on available surface sites. This interaction of ZDDP with dispersant and detergents not only impacts film thickness but also affects the composition.
Pages 8-13 go into detail too lengthy to recite here, but the gist of it is the three methodologies they use to measure the TCB. Using Auger, IR reflection absorption and Raman spectrometery, they go into very detailed descriptions about the measurement of the TCB layer thickness and how it changes with lubricant exposure.
I will confess, perhaps for the 1000th time, that I am not a chemist. I struggle at times to understand all the finite chemical interactions and their related affairs.
What I'm good at, what my study data shows, is analyzing data. And this shows that as OCIs mature, the wear rates go down precipitously.
What this (and other related) SAE study shows is WHY they go down.
Like many folks, you get too wrapped up in to the minutia of debate. I've said many times before I don't care about inputs; I care about results. If you filled a crankcase with a 50/50 mix of goat milk and dog urine, but still got very low wear rates, why would it matter what was inside? If you could use owl vomit mixed with killer-bee honey, and got great wear numbers, who cares? I do not, let me repeat, I DO NOT care one iota about the nuances of ZDDP, or any other additive in terms of their own existence. I only care about the end result of their interaction in terms of a goal; that of equipment longevity. Whatever produces low wear is what I seek. To me, there is a LOT of SAE information that shows the TCB is at work here. The TCB is altered negatively at the onset of an OCI. After about 3k miles, the TCB is fully re-established and does not change thickness much. This process represents a change in composition and thickness, and while never "gone", it does morph from stage-to-stage with the OCI. Once fully established, it provides a "near zero" wear rate. As the miles pile on, the very low wear events culminate in a desirable effect. What I have said, so many times before, is that inputs are only predictors, whereas outputs are results. If the wear data trend is low, then an OCI is favorable for continuation. Changes in inputs (vis shift, TAN inversion, FP reduction, etc) are only precursors that would indicate a need for closer scrutiny. They are, in and of themselves, NOT a reason to OCI.
What is clear is that this study, and many others, attribute the TCB with wear rate reduction. It certainly isn't vis or TBN/TAN; those are discounted. Honestly, I still don't understand your objections. I'm just to the point where I don't care about your frivolous points. There are multiple SAE studies that document the TCB and it's effects. You've not once given me any reason to think they are wrong. And all my data (from an independent point of view not related to chemistry, but wear data results) says they are right. I say this because I can show thousands of engines that use different lubes, but all have the same effect. Different lubes will have different chemistry add-packs, different viscosity, different environmental inputs, different drivers, etc. But the OUTPUT (reduced wear with OCI extension) is common. Lube thickness does not control wear rates nearly as much as TCB. Phos does not control wear rates nearly as much as TCB. ACID/BASE relationships do not alter wear nearly as much as TCB. And the list goes on ...
Originally Posted By: Shannow
The test isn't about any of the other pertinent factors that an engine oil is required to do with corrosion of dissimilar metals, starting, gellation...anything but a simple metal on metal tribometer.
I don't recall ever saying that it addressed anything but the TCB and wear (and friction). Even the study states at the outset this:
"These findings could be an enabler to achieving longer drain interval although several other factors must to be considered." (grammatical error is theirs, not mine).
Neither I, nor the study, ever said to ignore all input concerns and just flail away at a long OCI. There are concerns that must be monitored, for sure. But your statement here is just silly; never did I or the study state or imply that the study addresses anything but the TCB and wear and friction. You're off track yet again ...
You and I clearly interpret information differently. We shall have to agree to disagree, perhaps fervently.
I find these studies credible and offer an explanation as to WHY I see the results from my wear analysis.
I would encourage others to purchase the studies and read for themselves. They can make up their own mind.
dnewton, I would appreciate a look at the papers that demonstrate that the tribofilm is completely removed at oil change. I've never come across anything that demonstrates that you go back to virgin metal with an oil change, but am happy to be educated.
Please provide the numbers...I'll buy them myself.
I don't know that I ever stated the TCB is completely removed. I have said, and the study concludes, that the TCB is reduced significantly by a fresh load of oil. But neither I nor the study ever said it was completely gone. I have used the term "remove" (as do they in the studies) in a general sense; if you took it to mean completely and utterly devoid then I've given the wrong impression. It is not reduced back to "virgin metal"; it (the TCB) is significantly reduced.
From Page 7 ...
"Is is likely that the film will be removed ultimately or replaced by a different type of film, but it points to the fact that once the film is formed with a fully formulated oil, it is not removed very quickly. The existing film may affect the chemical mechanism for forming the new film which provided the reduced friction and wear rate benefit."
Further, the other studies incorporated by reference clearly describe that different formulation of ZDDP, reacting with different formulations of oil lube packages, will make for different rates at which the TCB will decay at an OCI, and rate at which it will form a new "skin" (layer, whatever you want to call it).
From page 3 ...
Film thickness is also dependent on oil temperature with higher temperatures tending to promote greater film thickness. However, when a dispersant is added, the film is removed and the film thickness stabilizes at a lower value. The antagonistic behavior of dispersants is well-known and one of the possible mechanisms was believed to be the competition between dispersant and ZDDP molecules to absorb on available surface sites. This interaction of ZDDP with dispersant and detergents not only impacts film thickness but also affects the composition.
Pages 8-13 go into detail too lengthy to recite here, but the gist of it is the three methodologies they use to measure the TCB. Using Auger, IR reflection absorption and Raman spectrometery, they go into very detailed descriptions about the measurement of the TCB layer thickness and how it changes with lubricant exposure.
I will confess, perhaps for the 1000th time, that I am not a chemist. I struggle at times to understand all the finite chemical interactions and their related affairs.
What I'm good at, what my study data shows, is analyzing data. And this shows that as OCIs mature, the wear rates go down precipitously.
What this (and other related) SAE study shows is WHY they go down.
Like many folks, you get too wrapped up in to the minutia of debate. I've said many times before I don't care about inputs; I care about results. If you filled a crankcase with a 50/50 mix of goat milk and dog urine, but still got very low wear rates, why would it matter what was inside? If you could use owl vomit mixed with killer-bee honey, and got great wear numbers, who cares? I do not, let me repeat, I DO NOT care one iota about the nuances of ZDDP, or any other additive in terms of their own existence. I only care about the end result of their interaction in terms of a goal; that of equipment longevity. Whatever produces low wear is what I seek. To me, there is a LOT of SAE information that shows the TCB is at work here. The TCB is altered negatively at the onset of an OCI. After about 3k miles, the TCB is fully re-established and does not change thickness much. This process represents a change in composition and thickness, and while never "gone", it does morph from stage-to-stage with the OCI. Once fully established, it provides a "near zero" wear rate. As the miles pile on, the very low wear events culminate in a desirable effect. What I have said, so many times before, is that inputs are only predictors, whereas outputs are results. If the wear data trend is low, then an OCI is favorable for continuation. Changes in inputs (vis shift, TAN inversion, FP reduction, etc) are only precursors that would indicate a need for closer scrutiny. They are, in and of themselves, NOT a reason to OCI.
What is clear is that this study, and many others, attribute the TCB with wear rate reduction. It certainly isn't vis or TBN/TAN; those are discounted. Honestly, I still don't understand your objections. I'm just to the point where I don't care about your frivolous points. There are multiple SAE studies that document the TCB and it's effects. You've not once given me any reason to think they are wrong. And all my data (from an independent point of view not related to chemistry, but wear data results) says they are right. I say this because I can show thousands of engines that use different lubes, but all have the same effect. Different lubes will have different chemistry add-packs, different viscosity, different environmental inputs, different drivers, etc. But the OUTPUT (reduced wear with OCI extension) is common. Lube thickness does not control wear rates nearly as much as TCB. Phos does not control wear rates nearly as much as TCB. ACID/BASE relationships do not alter wear nearly as much as TCB. And the list goes on ...
Originally Posted By: Shannow
The test isn't about any of the other pertinent factors that an engine oil is required to do with corrosion of dissimilar metals, starting, gellation...anything but a simple metal on metal tribometer.
I don't recall ever saying that it addressed anything but the TCB and wear (and friction). Even the study states at the outset this:
"These findings could be an enabler to achieving longer drain interval although several other factors must to be considered." (grammatical error is theirs, not mine).
Neither I, nor the study, ever said to ignore all input concerns and just flail away at a long OCI. There are concerns that must be monitored, for sure. But your statement here is just silly; never did I or the study state or imply that the study addresses anything but the TCB and wear and friction. You're off track yet again ...
You and I clearly interpret information differently. We shall have to agree to disagree, perhaps fervently.
I find these studies credible and offer an explanation as to WHY I see the results from my wear analysis.
I would encourage others to purchase the studies and read for themselves. They can make up their own mind.
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