old oil better than new oil

[Nickdfresh]

Oh dear... I have to blow the dust off my Greek Philosophy text in order to discuss motor oil here? Let's discuss the "Allegory of the Cave," much more interesting than Zeno's Paradox actually.

I understand the point, that one that thinks that absurdly short drain intervals adhered to by some as beneficial are completely wrong. I couldn't agree more. I was more than happy to go 5000 miles when using Mobil1, in fact I think that time rather than miles seems to be the biggest factor in changing oil. I'd go even longer next time with a newer vehicle actually. But doesn't older oil allow a build up contaminants in the engine? I'm merely questioning the validity to real world applications for a daily driver that starts their car up every morning and runs it periodically during the day. Seems to me that this would be difficult to simulate or keep track of with any empirical validity over the life of an engine, one of my problems with the Consumer Reports famous "NYC Taxi-Cab" study, where cars were running at operating temp. nonstop... BTW, I agree that it's silly to change oil too frequently, as it is to try to squeeze out every last mile or kilometer out of motor oil, when you routinely pay far more to fill the car up with gas every week or two than you do to change your own oil every three-to-six months...

I'm just wondering, what's the real world application to this? When should oil be changed then? How do we know? UOAs? Approximately, when is the best guess when oil losses it's effectiveness and "needs to be changed?"

 

[ScottB]

Another questions is: "what is the range that the oil is better" if the research above is to be trusted?

At what point does the "good used oil" become not as good?
If we were all to agree that both extremes are bad, how wide is the real range of oil in terms of miles?

It is from 1000-5000 miles?
Is it from 1200-3500 miles?
Is it from 2000-6000 miles?

Where do we go from here?
Where does one buy oil (aside from people like me) that has been "broken in" but not over-used?

Scott

 

[Winston]

Scott,

Let me first agree that there are many factors to consider when changing oils. I gave two examples that support the contention that used oil causes less "wear" than new oils. You did not ask for "conclusive" evidence. That would be the holy grail, and I for sure do not have it. I did provide two solid pieces of evidence. You can dismiss it if you want because I have not determined the mechanisms, filter involvement, etc. "...If the finding is verified, the mechanisms should be determined, and ramifications with respect to oil change intervals, filter involvement, and additive packages should be considered..." However, the evidence is still valid, whether or not I know the mechanism.

As far as your comment on 1999. 1999 was not in the dark ages. SWRI's testing methods are very scientific.

You can continue to ask more questions, and I will freely admit that I do not have all the answers. However, why don't you at least respond to the two pieces of evidence that I supplied.

All the evidence I have seen points to the conclusion that moderately used oil causes less wear. Do you have ANY evidence that shows that moderately used oil causes more wear? Please reveal it because I have not seen it.

quote:

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I'm just wondering, what's the real world application to this? When should oil be changed then? How do we know? UOAs? Approximately, when is the best guess when oil losses it's effectiveness and "needs to be changed?"

---

This is a good question. However, there is no evidence to support the contention that 3k/3mo is the right answer. Nor is there evidence to conclude that shorter OCI is always better.

 

[ScottB]

Actually, back a few posts, I conceded that I could understand that slightly used oil with metal particulate in solution (suspension may be a better term) could help against ware.

But, none of this takes into account the other functions of oil - to cool, clean, and seal. Are all aspects of used oil better in the middle?

I don't know. I'm not trying to reach an end to this thread, merely contribute some thoughts.

All things considered, I can understand the theory behind this, but I also feel that used oil has other negative properties that I'm not willing to leave in my car.

All in good fun and in the interest of learning, I'm enjoying it.

I do notice though that some of you on the "other side" tend to get personal about this thread. I've not attacked anyone, but some of you seem pretty peeved at us 3k-ers.

Scott

 

[Winston]

quote:

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I do notice though that some of you on the "other side" tend to get personal about this thread. I've not attacked anyone, but some of you seem pretty peeved at us 3k-ers.

---

I get a little to worked up when I argue sometimes, but I never mean to be personal, just pointed.

As far as the 3k people, it is just the ones that say " why worry about it, it is cheap insurance" are the ones that bug me.

In general, I have seen evidence that older oil reduces wear. GM spent a lot of money on their OLM and evaluated TBN, ZDDP depletion, dispersion effectiveneess, and they have some pretty long OCI's with Dino. I think there are benefits to synthetic that cannot be achieved with dino oils (cleanliness, additive quantities). I see no evidence from my UOA's to make me think that I am near the limit of any of my oils good properties when I go 7500 miles on the oil. Plus, I think I am getting a little less wear than if I changed at 5k miles. I am within the warrenty requirements. So, I use a good synthetic, with a good filter, and go 7500 miles. To me, that is a perfect balance. Plus, by doing fewer oil changes it leaves me time to maintain all of the other fluids in my car, as well as keep it nice and clean on the outside and inside.

 

[ScottB]

Well then, we've reached an agreement, of sorts.
I may very well go to 5k if my gut and possibly a UOA show me 3k is too soon.
I have a 4-banger, and I sit in hot LA traffic twice a day, so for me, even M1 might be taking a lickin'

I think that if there's validity to the slightly used oil is better evidence, that someone would have come up with a way to simulate this in the refining process and use it.
OTOH, it is possible that modern additives make up for this?

My point about the studies being done in 98/99 wasn't to discredit them, but you have to admit that oils have likely changed quite a bit in 7-8 years.

Scott

 

[AstroVic]

quote:

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Originally posted by 99:
If anyone local to me wants my old oil and filters, they're yours for the taking. I have....available to those that really buy into this "old oil is better than new oil" B.S.

---

Give it up, 99. I've proposed that at least two or three times on here and nobody will bother to answer. It's funny how everyone wants to go on and on about the scientific theories of this and that, but those same people wouldn't dare pour my used oil in their newer model BMW, Porsche, Mercedes, etc.

I even offered to pay $10 to the first person who showed up to my house and poured my used oil in ANY decent late model car. I even offered to perform the labor and to provide a new Wix filter for their car.

Still no takers.

But, hey, used oil must be better than new oil because my quantum physics teacher told me about some theory regarding....(blah, blah, blah).

 

[JAG]

Nobody wants your used oil, for the nth time. If you don't like scientific discussions, don't read them or post in them.

 

[Bryanccfshr]

Why is this so hard to comprehend? No one wants to run used drained oil not knowing if your engine is contaminated with coolant or otherwise.
The question is if engine conditioned oil that is still free of excessive insolubles with adequate active additives remaining is providing better wear protection.
The practical application if the answer is yes would mean that by extending OCI's without overly depleting the oil would provide for less wear than shorter OCI's.

 

[Gary Allan]

quote:

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that someone would have come up with a way to simulate this in the refining process and use it.
OTOH, it is possible that modern additives make up for this?

---

Scott, the study was designed to give you the impression that you're hurting your engine with traditional short OCIs ...or rather... how longer OCIs would appear to make more sense if the owner's goal was minimal wear.

It was (my speculation) an inducement for those who cling to the older religions about a healthy engine. As I said, most studies are done to support some trend/policy/evolution where the consumer is asked to accept something that is a departure from that which they regard as canon in the story of automotive related issues.

You sware by 3k/3m ..the industry has determined that this is a wasteful practice. They give you a reason to change your mind.

I'm sure that there are ways to nail this down ..or at least answer a few things ..but we really don't need to. Regardless of some transitional convulsive states in the maturation process of oil ..we've seen tons of data that shows that the oil itself is vital and suitable for continued use in 1000's of UOAs. Your wear metals will more indicate the proper oil for the application ...but as long as the oil is still oil (within spec visc, tbn, insolubles, fuel dilution, moisture, etc.) then there is no rational reason to change it.

Do you see what I mean here? The two aren't necessarily related ..at least in the way we commonly think. A resilent oil may be the wrong oil for the application ...yet not suffer at all from it. The engine will do that (maybe).

 

[GMorg]

Anyone that designs a study with goal of getting a particular answer should not be allowed to design studies. The goal of any good science is to determine answer. The answer is neither good nor bad, it is just the answer.

In this case, since the study would never be done, the design was get people to think about how oil changes over time (as it is used) as opposed to thinking about "used oil" as only dirty and exhausted. I had hoped that we could discuss the possibility that oil protects best at some point beyond the first day of use. If we could determine the range of time/mileage in which oil protects best, then we could know (as opposed to having a conviction based on faith or myth) the range of time that would be best, generally. (And again, for those with short attention spans, I recognize that the "best" will not apply to all situations.)

A correlative to the above discussion is the possibility that those that do very short OCIs (1000-2500 miles) may have actually be inducing MORE wear, over time, than those that do OCI of 3000-5000, or more miles.

Intuition suggests that fresh is better. Some people are motivated by intuition and change oil very frequently. I suppose that I am asking people to consider wether they are most comfortable making desicions base on intuition or based on data and thoughtful consideration. If there are thoughtful people that are grounded in the "real world", in the world of observable data, and these people are doing very short OCIs, I thought they may want to consider that longer OCIs may be better for them - their choice.

For those that are motivated by what their dad did, or what they have always done, or what Madison Ave. has taught, well science is irrelevent. If you trust your feelings and emotions more than your own intellect, then I suggest that you know more about how you should make decisions than I know about how you should make decisions.

For me, data is data. When a data set is counter-intuitive or or counter to one of my convictions, I have to reconsider my convictions. Data does not lie. I would also rather be thoughtful and wrong than faithful and wrong. (And yes, I think that most of us would rather be correct regardless of decision strategy) I just prefer that when I am wrong, it is not because I did not THINK about.

 

[toocrazy2yoo]

Well, G, does the above suggest I've changed too often (three times, Dino, 100, 500, 3000 miles) the first 3000 on a new car? My goal was to remove the factory swill, break-in metals, casting sand, etc, etc from the manufacturing process. At the 5K mark, it's M-1, new OEM filter, and a 5K OCI. Engine is a 1.6 DOHC.

So, have I laid the groundwork for lesser longevity with the OCI I've run so far, or does the flush of break-in debris trump the additional wear of keeping such new oil in the car for the first 5000 miles?

 

[GMorg]

toocrazy2yoo,

I think that if you have metal-filled, sand-filled oil, then you should probably change it. I don't know that you actually did have metal-filled sand-filled oil, but if you did, that would not be the type of "used" oil that I have attempted to discuss.

To all:

I apologize if I have somehow communicated that abrasive oils, corrosive oils, or coked oils may be better than new oil. Perhaps I am the butt of some sort of joke. I don't know. I would have never guessed that I have presented a difficult concept. Engine break-in seems to be accepted here. Oil break-in, is apparently much more conceptually difficult. Maybe that is the parallel to make. New engine has potential, but not quite at its best yet. Broken-in - sweet. Worn-out, spun bearing, lobeless cam - bad. I am suggesting that it might be possible that trashing oil at the end of very short OCIs may be like trashing a motor as soon as it is broken in well.

 

[Gary Allan]

quote:

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Anyone that designs a study with goal of getting a particular answer should not be allowed to design studies. The goal of any good science is to determine answer. The answer is neither good nor bad, it is just the answer.

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I may agree with you in principle here, GM ...but the background noise tends to discount your tenet of good science.

This was an observation. It may or may not have been a KNOWN characteristic of ALL oils (maybe NOT) in the course of their life in OCIs that extend beyond a certain point. The implication is that there can be more harm then good by doing shorter OCIs ...or that, by reducing the number of oil changes, you can avoid a significant number of these transitional events and the implied wear that would be included.

This data is not stated for its own sake. It is displayed to provoke a desired effect ..or at least provide a viable pathway for a favorable behavior. It begs for a desired conclusion to be arrived at. It's the "HEY LOOK!!! (smaller print) What do you think?".

Are you aware of any studies that counter current favorable neo-dogma formation?? At least any that are brought to the surface??


It's like any number of suggestive instances in our media that throw on "and that's good for the enviroment" ..just to give you the warm and fuzzy feeling.

Now I'm not saying that this is the case here in the study that we are commenting on. I truly think that there are way too many people using way too much oil for the utility that they get out of it. I think that they outpace those who neglect their engines.

That is, this study speaks the truth ..but it may not represent the reason that the truth is stated. It's like screaming that the erosion of the Cape Cod beeches is a shocking event ...while failing to mention that the erosion is a natural event.

 

[427Z06]

Good points, Gary. Kinda' like:

Don't you want the best for your child?

or

It's interesting that Ford held closed door sessions with police departments when discussing 5w20.

Comments or questions to influence your perceptions.

Here's another point to consider. Take UOAs from a healthy engine at both 3,000 mile and 6,000 mile intervals. Assume that both samples are still considered serviceable according to the UOAs. Take the PPM of wear metals/K-mile for the for each and multiply them out to 300K-400K miles. Look at the difference of total PPM of wear metals. Does anyone believe that given the differences in total wear metals, you'd actually be able to measure differences after 300K-400K miles in actual engines in service? That is, if you tore down the engines, measured, weight and inspected them, that you'd actually find a significant difference on the wear of the parts?

If you ran such a experiment, there would be of course a bunch of variables that would have to be constrained. Most likely the longevity of million mile engines are due to the operating conditions, not due to frequent changes. You'd think the quick-lube(3K/3K) interests would be served if they would commission someplace like Southwest Research to carry out such a experiment under a number of real world conditions. Anybody aware of such an experiment?

 

[ScottB]

Data may be data, but all data is not GOOD data.
I did research for 13 years at UCLA and I can say that studying anything involves careful thought and sound methodology.

"Research" is a term that is used as gospel for some. Research can be good or bad, and as was said, if you do it to prove your point as opposed to finding the answer(s) you're in the wrong biz.

Scott

 

[GMorg]

427z06,
You have hit the nail on the head. I don't have access to enough of the type of data to which you refer to come to any conclusions. However, if you use the Amsoil portion of the paradise garage effort and compare 2K oil changes to 6K oil changes, the difference in iron and copper wear would be in the ball park of three fold more wear in the 2K lifetime OCI compared to 6K lifetime OCI. Lead on the other hand appears to be linear over a long OCI. As a result, one would not predict any difference between the two strategies for lead wear. I excluded the Mobil 1 data because the early wear may be confounded with break-in. If you also consider the Mobil 1 data, then the 2K vs 6K strategy is at least 50% more wear in the 2K lifetime OCIs.

Some contributors to this thread have suggested that the spike in copper and iron are artifactual and the result of "cleaning". I cannot exclude that possibility. However, given that in model systems that friction and wear appear to go down after an oil has been used, I am also left considering if the "broken-in" oil (to not use "used oil" as a term) is actually better. Among the more interesting theories as to what happens with broken-in oil is the idea that it is simply sheared and that lower viscosity results in lower friction and lower wear in the models used. (I am more than happy to stay with "the models used" statement for now. I understand that there are diffences between any model and what it does or doesn't model.)

As for ScottB, I have just begun my 20th year in research (Academic, then government, and now industrial) and I agree completely with your last post. If I implied otherwise, I appreciate your correction.

 

[ScottB]

GMorg: Not meant as a correction as much as an addendum for others...
I grew up in a time where people actually said to "read books - they are the only way to learn the truth"
As if to say, "TV is bad, you can't learn watching the boob-tube"

Of course, there are at least as many bad books as there are bad TV shows

Then internet can be the new "boob-tube" in that respect. Lots of bad and good info - you gotta figure out which is which...

Scott

 

[427Z06]

Not to start a new topic to debate, but there are examples of "bad research". The EPA study on secondhand smoke is one:

http://www.straightdope.com/columns/000602.html

They fudged the statistical analysis to get the numbers they wanted. Further, many inconclusive research papers point back to this research paper to arrive at a conclusion. Note: I'm not an advocate of secondhand smoke. I'm just illustrating that there are cases where the desired outcome can influence the end result.

I believe there is equally flawed conclusions drawn from Aspartame studies too. Those are but a couple of examples.

 

[Bryanccfshr]

427Z06,

Not to drift this too far off topic but those are excellent examples of goal driven research. It seems that complete objectivity is not as common as we would like to believe. We can get into all kinds of scientific debates (ie global warming etc) because we cannot trust the objectivity and intelectual honesty of all funded research. (researches need job security too)

As far as the engine conditioned oil goes it is hard to find conclusive evidence that used oil alone causes less wear because so many other factors could be influencing UOA readings.
I certainly don't see more wear as a result of moderate to not too long OCI's, nor do I see it with extremely short ones (dry start events excluded).