Does conventional oil protect better?

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Originally Posted By: OVERKILL
Originally Posted By: Nederlander75
OP, Blackstoe compiled a good bit of data a couple years back that revealed that conventional 5w30 did, in fact, provide lower wear metal numbers over the sampling of their database than all synthetics except Amsoil. However, that oil was barely in front of good ol GTX so for the $ it was quite profound that conventional was far and away the better choice for most drivers.


Those numbers don't correlate directly to actual wear though, to be pedantic. An oil that kept particulate in suspension better than another is, by definition, going to show higher levels of that particulate when sampled. Just as an example as to how that can go wrong. Used oil analysis is not a tool designed to measure wear, simply one to measure the life and condition of the lubricant and check for contamination. Controlled tear-down testing is the proper tool for measuring wear.


Are we saying that Synthetic holds particulates in suspension better than Conventional? Sincerely interested. Interesting thread.
 
This was done by Consumer Reports some years back and IIRC it showed no appreciable difference. However I remember thinking the test was flawed as it was done in a taxi fleet, and while they do see severe service, they don't see many cold starts.
 
Originally Posted By: wemay
Originally Posted By: OVERKILL
Originally Posted By: Nederlander75
OP, Blackstoe compiled a good bit of data a couple years back that revealed that conventional 5w30 did, in fact, provide lower wear metal numbers over the sampling of their database than all synthetics except Amsoil. However, that oil was barely in front of good ol GTX so for the $ it was quite profound that conventional was far and away the better choice for most drivers.


Those numbers don't correlate directly to actual wear though, to be pedantic. An oil that kept particulate in suspension better than another is, by definition, going to show higher levels of that particulate when sampled. Just as an example as to how that can go wrong. Used oil analysis is not a tool designed to measure wear, simply one to measure the life and condition of the lubricant and check for contamination. Controlled tear-down testing is the proper tool for measuring wear.


Are we saying that Synthetic holds particulates in suspension better than Conventional? Sincerely interested. Interesting thread.


Nope, I'm saying an oil that is more expensive to blend and geared to be a better product likely will. That product doesn't have to be synthetic, just a premium product. Most premium oils are however synthetic, so they likely do contain higher concentrations of dispersants and the like. This would be even more the case for a product designed for extended drains, since that function need to be maintained for the longer OCI.

A dual-rated HDEO would be an example of a conventional oil that would/should have higher levels of these additives in it due to the longer drains these oils are designed for and having to deal with soot.
 
If the metals part of a UOA includes the particulate fraction, however defined, that'd potentially be a seriously uncontrolled variable.

If, say, you were getting ferrous metal settling out of your oil, (As I was. Not sure of the current status after a couple of oil changes and sump cleans) the amount in a sample would be heavily influenced by the sampling procedure and subsequent handling, especially settling times and shaking.

That's mostly out of the control of the commercial lab doing the analysis.

I suppose they could do a spin or filtration to take particulates out but that'd remove some evidence.
 
This discussion has come up a lot, as to what is the maximum particle size detectable via ICP or AA. The answer has always been that it is relatively small.

Originally Posted By: Ducked
If the metals part of a UOA includes the particulate fraction, however defined, that'd potentially be a seriously uncontrolled variable.

If, say, you were getting ferrous metal settling out of your oil, (As I was. Not sure of the current status after a couple of oil changes and sump cleans) the amount in a sample would be heavily influenced by the sampling procedure and subsequent handling, especially settling times and shaking.

That's mostly out of the control of the commercial lab doing the analysis.

I suppose they could do a spin or filtration to take particulates out but that'd remove some evidence.
 
Originally Posted By: Ducked
Originally Posted By: BrocLuno
Over in technical papers forum there is an ongoing discussion about wear metals, especially upper cylinder wear on straight SAE 30 HD vs multi-viscosity oils on cold start.


Link? Had a look and didn't see it.


Can't find it, but went back to an SAE 30 thread and have this: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4156436/4

Shannow may have it linked better somewhere ...
 
Lets put it is a simple way that even those fooled by the marketing should be able to understand and
I like syn oils especially in drive lines. The over the road semi trucks are getting a million + miles on their $50,000 engines use convention oils that we all can but at Walmart. Syn oils have their advantages and are prescribed for those uses. I first used dyn oils in 1960 Stten C chemical lube in my 1968 Yamaha. And still do in some of the Vehicles I take care of.
 
Looks like it to me
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SAE082807.jpg
 
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BrocLuno,

Have you actually read the 21 year-old SAE paper (or the part II follow-up from the same individuals three years later, refuting some earlier positions), this originates from, or are you just blindly posting up a graph without any source attribution, and providing your own interpretation of what you think it demonstrates?
 
Originally Posted By: Ramblejam
BrocLuno,

Have you actually read the 21 year-old SAE paper (or the part II follow-up from the same individuals three years later, refuting some earlier positions), this originates from, or are you just blindly posting up a graph without any source attribution, and providing your own interpretation of what you think it demonstrates?


What do you think?
 
When I dealt with auto manufacturers and race engine managers in the past, none of them would accept a wear metal count from an oil analysis as an indicator of wear. In the end, there were some race engine managers that would accept weighing the actual metal left in the oil. Getting the metal weight left in the oil turns out to be an expensive test, probably about $3000 today. It seems kind of stupid when the race engines are going to be taken down anyway! The manufacturers either accepted engine tear down with inspection or the radioactive treatment of certain components and then measuring the oil with some form of a geiger counter. I never actually performed the radioactive type of test.

Really a subject for another thread, but where do people get the idea that UOA wear metal particle counts accurately predict engine wear? It seems logical, but I know of nobody in the industry that accepts this type of analysis as an accurate indication of wear.
 
I few years back Buster posted commentary from Mobil regarding UOAs with them saying outright that metals in UOA were indicative of engine wear. This was presented by him at that time regarding the higher FE levels in M1 UOAs.
 
I have actually read the paper. And I do concede that it is for oil formulations that have 1.) been superseded, and 2.) were for diesel engine applications (Mercedes IIRC...), 3.) also involved non-complete additive packages with lab grade partial oils (in other tests than the one graphed). This is the same paper that demonstrated the causes of upper cylinder wear (mostly condensation and corrosion).

I am interested because I live in a climate where straight SAE 30 HD is quite doable. I keep looking for a more modern paper that involves current chemistry and formulations. But such a paper does not seem to be forthcoming ...

However, their point that VII's do not contribute to actual lubrication is valid. They ultimately are basically either carriers or simply space users. In the case that they are carriers, they do help actual oil get to the needed surfaces. In the case of straight SAE 30, there are no VII's so it's all oil, all the time. Whatever film exists is pure lubrication
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Does it apply to conventional vs synthetic - it may ... It all depends on how the oil are formulated. Some synthetic blend still rely on a healthy slug of VII's to make their range ...

Back in the day when I was in Marine Engineering, we did UOA's on ships and launch's oils all the time. We looked at ratios of various metals to inform of POSSIBLE wear, not actual wear. It's a pointer, not a scalpel ...
 
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Originally Posted By: Nederlander75
I few years back Buster posted commentary from Mobil regarding UOAs with them saying outright that metals in UOA were indicative of engine wear. This was presented by him at that time regarding the higher FE levels in M1 UOAs.


I could have sworn it was just the opposite. Do you have a link? I'd love to see it. I read comments like it was cleaning up and releasing wear metals trapped in remote areas of the engine, freeing them from sludge, etc. etc.
 
Originally Posted By: demarpaint
Originally Posted By: Nederlander75
I few years back Buster posted commentary from Mobil regarding UOAs with them saying outright that metals in UOA were indicative of engine wear. This was presented by him at that time regarding the higher FE levels in M1 UOAs.


I could have sworn it was just the opposite. Do you have a link? I'd love to see it. I read comments like it was cleaning up and releasing wear metals trapped in remote areas of the engine, freeing them from sludge, etc. etc.


While I was ACTIVELY investigating the ferrous metal settling out in my oil, I took my oil pump apart to see if it was wearing badly.

Seemed OK but there was a sludge filled void in the casting.

I concluded that this kind of thing could make any deductions about current wear levels from current oil quality almost impossible, since sludge could be washing out of "historic" stores.
 
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Originally Posted By: Ducked
Originally Posted By: demarpaint
Originally Posted By: Nederlander75
I few years back Buster posted commentary from Mobil regarding UOAs with them saying outright that metals in UOA were indicative of engine wear. This was presented by him at that time regarding the higher FE levels in M1 UOAs.


I could have sworn it was just the opposite. Do you have a link? I'd love to see it. I read comments like it was cleaning up and releasing wear metals trapped in remote areas of the engine, freeing them from sludge, etc. etc.


While I was ACTIVELY investigating the ferrous metal settling out in my oil, I took my oil pump apart to see if it was wearing badly.

Seemed OK but there was a sludge filled void in the casting.

I concluded that this kind of thing could make any deductions about current wear levels from current oil quality almost impossible, since sludge could be washing out of "historic" stores.

That coincides with what I recall reading about M1 and higher wear metals. I concluded it was from those "sludge filled voids" you mentioned.
 
Originally Posted By: Nederlander75
I few years back Buster posted commentary from Mobil regarding UOAs with them saying outright that metals in UOA were indicative of engine wear. This was presented by him at that time regarding the higher FE levels in M1 UOAs.


I believe this was the other way around. Mobil stated that engine wear could not be gleaned from a UOA. I also believe buster posted about an F1 team that used UOA's with their custom blended lubricant, but again, this was on a specialized piece of machinery with highly controlled conditions and materials as well as massive trending in place. Definitely not relatable to firing off a UOA to Blackstone.
 
Originally Posted By: carock
The manufacturers either accepted engine tear down with inspection or the radioactive treatment of certain components and then measuring the oil with some form of a geiger counter.


Probably a scintillation counter, but however its done, I don't quite the difference in principle between the radio-labelling technique and (presumably spectrochemical) oil analysis. They both measure material in the oil.

The radio-labelling is probably more sensitive, and the source of the material could be more precisely and unambiguously identified, but the significance of, say, iron or radio-labelled iron in the oil seems about the same.

If there isn't any iron in the oil formulation it has to be the result of wear, surely?
 
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