UOA article - what is "normal"

Posted by: dnewton3

UOA article - what is "normal" - 10/23/12 04:59 AM

http://www.bobistheoilguy.com/used-oil-analysis-how-to-decide-what-is-normal/
Posted by: A_Harman

Re: UOA article - what is "normal" - 10/23/12 08:10 AM

Is that an article that you have just posted, or has it been on BITOG for a while? Regardless, thanks for the educational read!
Posted by: Samilcar

Re: UOA article - what is "normal" - 10/23/12 08:41 AM

Great article.
Posted by: dnewton3

Re: UOA article - what is "normal" - 10/23/12 11:35 AM

Originally Posted By: A_Harman
Is that an article that you have just posted, or has it been on BITOG for a while? Regardless, thanks for the educational read!


Wrote the bulk of it this month on vacation; been in editing and formatting for about a week.
Posted by: ltslimjim

Re: UOA article - what is "normal" - 10/23/12 03:27 PM

Very nice. thumbsup
Posted by: DanMiller

Re: UOA article - what is "normal" - 10/23/12 05:49 PM

Very good article, what oil do you like based on all of the UOAs you have seen ? Are you a thick or thin oil believer ?
Posted by: OVERKILL

Re: UOA article - what is "normal" - 10/23/12 06:19 PM

Excellent article thumbsup
Posted by: JAG

Re: UOA article - what is "normal" - 10/23/12 06:35 PM

Thank you for the great article, Dave!
Posted by: buster

Re: UOA article - what is "normal" - 10/23/12 07:12 PM

Thanks Dave! thumbsup
Posted by: DanMiller

Re: UOA article - what is "normal" - 10/24/12 12:35 AM

Since leaving Oil in longer is better for wear numbers would it make sense to change the Oil filter in between Oil changes ?
Posted by: Clevy

Re: UOA article - what is "normal" - 10/24/12 01:12 AM

That was a great article. Very enlightening. Wear rates going down as the oil gets more miles was very informative. Thank you for the enlightening information.
Posted by: fdcg27

Re: UOA article - what is "normal" - 10/24/12 06:13 PM

Really informative.
We here tend to get all excited about small differences in wear metals per thousand miles, but you have put it in perspective.
Maybe the only real use of UOAs is to find gross anomalies, like coolant leaking into the engine oil, or TBN and TAN as well as shear to determine oil life.
Posted by: Quattro Pete

Re: UOA article - what is "normal" - 10/24/12 07:50 PM

Originally Posted By: DanMiller
Since leaving Oil in longer is better for wear numbers would it make sense to change the Oil filter in between Oil changes ?

Why? Filter efficiency increases with age/miles as well.

Only if you have a seriously sludged up engine that you should change filter more frequently, but then you should not be running extended OCIs either.
Posted by: HTSS_TR

Re: UOA article - what is "normal" - 10/25/12 01:22 AM

Originally Posted By: Quattro Pete
Originally Posted By: DanMiller
Since leaving Oil in longer is better for wear numbers would it make sense to change the Oil filter in between Oil changes ?

Why? Filter efficiency increases with age/miles as well.

Only if you have a seriously sludged up engine that you should change filter more frequently, but then you should not be running extended OCIs either.

I agree. I'm thinking about leaving cartridge oil filter in the E430 for 2 OCI's of 10-12k miles each OCI. I will inspect the oil filter carefully on the next oil change and re-use it if the filter is in good shape and I don't see any debris. The capacity of the fleece filter is more than 10 grams, it is not possible for the engine to generate more than 2-3 grams in 10k miles.
Posted by: dnewton3

Re: UOA article - what is "normal" - 10/25/12 04:52 AM

The only way to know for sure it to get some PCs done (particle count analysis).

However, I would contend this; the OEM typically is as conservative with the FCI as they are the OCI.

There are a few notable exceptions. One such example is my (new to me) 2000 Galant with 2.4L engine. The "normal" OCI is 7.5k miles and the FCI is every other oil change, hence every 15k miles. That is with any filter that meets their OEM specs. And there are a whole host of filters from Purolator, Wix, Fram, etc that meet/exceed those specs, right on Wally's shelf. I am not saying all FCIs can be extended that far, but I am saying that as long as your UOA is showing good lube and engine health, the FCI should be able to at least go as long as the OCI. Only if your soot/involubles/oxidation were the drastically escalate in the UOA, would it indicate a need for FCI.

For my vehicles in warranty, (which I'm now down to only one), I am following the OEM criteria for O/FCIs. But for my other stuff, I'm beginning to push even the "normal" OCIs out and using the same filter for that duration.

I am going to put my money where my mouth is, too. I have an upcoming trip out west; we'll be taking my 1995 Villager that has 225k miles on it, and an estimated 6k on the oil by the time we leave. I expect it will have near 10k miles on the lube when we return. I look forward to seeing the UOA when I get back. Am I nervous? You bet I am; I'm always nervous a bit when I try something new. But I have faith in my data streams and SAE studies I've read. This is solid science; just because it's hard to believe, do not make it untrue.
Posted by: DanMiller

Re: UOA article - what is "normal" - 10/25/12 09:47 AM

Interesting, I would have thought changing the filter would be good. I have never heard that the filters become more efficient
I would assume you guys are taking about a higher quality filter.
Posted by: dnewton3

Re: UOA article - what is "normal" - 10/25/12 09:56 AM

Actually, just about any filter will become "better" with age.

Now - first we have to exclude situations where filters are used TOO far, or are WAY too old.

But in "normal" use, just about any filter increases it's efficiency. Simple explanation; as the media loads up, it closes down the pore size to ever tighter openings, thus reducing the size of particle that can pass through the next time. It's a self-fulfilling prophesey; the more it traps, the smaller particle it can trap, which goes round and round ...

Only if the media were to become blinded off to a point where th bypass were to open frequnelty/always, would there be an issue. That is typcially much further out than folks think.

Ironically, we are programmed as a society to always think that "new" is "better". In some examples, I would completely agree with that. "Newer" engine designs certainly are "better"; they run cleaner, get better fuel economy, and have more power density per displacement. And "newer" oils are also "better"; oils that are made today have stronger add-packs, and more robust base stocks due to refining and manufacturing capabilities.

But dumping in "new" engine oil and putting on a "new" filter (say every 3k miles versus every 7.5k miles) really does not achieve what folks think it does. As oil ages in the crankcase, and filters catch more particulate, they both actually improve as the miles pass.

And that is particularlly what this article shows. Between the SAE studies, and my data bank evidence of many thousands of UOAs, wear rates actually do go down as the lube system matures. It is beneficial to leave the oil in place as long as practical; there is litte benefit to changing oil often on some blind-obedience schedule.
Posted by: DanMiller

Re: UOA article - what is "normal" - 10/25/12 04:26 PM

Interesting your explaination makes alot of sense, have there been any studies that back this up ? I would be interested to read them ( not that I don't believe you ).
Posted by: dnewton3

Re: UOA article - what is "normal" - 10/26/12 04:39 AM

Plenty of studies in the SAE catalog; go to their site and buy what you will. I have purchased many over the years.
Posted by: fpracha

Re: UOA article - what is "normal" - 11/05/12 04:56 AM

Originally Posted By: dnewton3
But dumping in "new" engine oil and putting on a "new" filter (say every 3k miles versus every 7.5k miles) really does not achieve what folks think it does. As oil ages in the crankcase, and filters catch more particulate, they both actually improve as the miles pass.

And that is particularlly what this article shows. Between the SAE studies, and my data bank evidence of many thousands of UOAs, wear rates actually do go down as the lube system matures. It is beneficial to leave the oil in place as long as practical; there is litte benefit to changing oil often on some blind-obedience schedule.
Incredible revelations and thanks for your scientific writeup!
So for the sake of an engine's operating efficiency, in your experience, is your article also proving that "as thin as possible" is the best oil to use in an engine ?
or is it so that such a conclusion cannot be drawn from your collective data and SAE research papers?
Posted by: dnewton3

Re: UOA article - what is "normal" - 11/05/12 06:17 AM

The SAE paper (2007-01-4133) specifically notes that there is a vis increase, and that increase is non-detrimental at the valve train. However, it also acknowledges the concerns of fuel economy from parasitic drag in the cylinder, where surface area affected by vis is much greater than at the valve train.

In short, it's a balancing act.

The thing I'm trying to get across to people is that shorter OCIs generally are a total waste of money. You don't "gain" any wear reduction; you actually increase wear in shorter OCIs. While it may be counter-intuitive to the layman, it makes sense when you see the studies and data.

There are certainly times when shorter OCIs are warranted; heavy contamination or sludge. But those are not nearly as common as some believe, and I have always excluded such examples from my generalizations. I would NEVER suggest extending an OCI when there is a known problem that cannot be mitigated without phsical intervention, or stalling with OCI frequency. And that is really what it's all about; you have to KNOW your equipment, and your lubes, to really understand what is good/bad decision wise. Too many people here blindly take a "kitchen sink" approach; they throw everything at the lube interval (short OCIs, syns) and call it "good" and they have no idea how define acceptable condemnation limits, and are unaware of how far out even conventional lubes can successfully go.

As I've said (and it's in my signature line) ...
ANY lube can be over or under utilized.
Posted by: wemay

Re: UOA article - what is "normal" - 11/07/12 10:41 AM

Fantastic article, thanks for sharing.

This is why i use Mobil Super 5000 or PYB 5W30 conventional in my Mitsu Lancer Ralliart Turbo. The vehicle is a daily driver (no modifications, no track use, very rare spirited drive). Now, because it is a turbo, and under powertrain warranty, i subscribe to a 3750 f/oci. There are huge battles on the Turbo forums between conventional vs synthetic oil users. I am not saying that conventional is better, it isn't. But also isnt neccesary for my application, oci or driving style. Mitsubishi and all the major oil giants list conventional 5w30 as the requied oil. I just make sure it meets API SN, GF-5 ILSAC.


Again, thanks for sharing.
Posted by: Garak

Re: UOA article - what is "normal" - 11/08/12 02:24 AM

Dave, I was doing some thinking about the deposition of anti-wear films with respect to the oils we see now compared to what was seen a couple decades ago. Now we see that the anti-wear protection does better much further into the OCI. I'm wondering how much of that is due to the lower ZDDP oils we see. Also, we certainly see some very high ZDDP applications for break in lubes. I'm just wondering how things might have compared back in the day, with, of course, some consideration of the fact that oils were much poorer back then, too.

As an aside, I do think we place too much stock into how much ZDDP was in the older oils. Some certainly had some high levels, but a lot of them (check Blackstone's articles) had the same as PCMOs today, or even much less. Back then, ZDDP content was a bit of a gamble, even with the top brand oils. Today, at least, you know you're going to get in the neighbourhood of 750 ppm, with few exceptions.

Just because the phosphorous limits didn't exist back then didn't mean oil companies made sure all oils had 1400 ppm ZDDP, either.
Posted by: dnewton3

Re: UOA article - what is "normal" - 11/08/12 05:13 AM

When reading the SAE study they mention there are actually several different types of ZDDP compounds that can be used. The chemical make-up of the ZDDP does indeed affect the anti-wear layers. It also disucsses the affects of detergent packages reacting with the ZDDP and having a negative affect on the anti-wear layer.

Ryan Start (Blackstone) ran an oil in his truck that had zero ZDDP whatsoever; the package was formulated in alternative ways. I think it was an aero-oil, IIRC. Anyway - after a couple short OCIs, there was no abnormal wear due to the lack of ZDDP. The wear that was present was due to two things:
1) the old 350 GM simply is a high-wear engine to begin with (see proof in my article)
2) the engine was a new rebuild - break in was occuring

So the "need" for ZDDP is greatly overblown in his opinion, and in mine. Wear can be attenuated by a large multitude of methods; ZDDP is just one of them. And while "ZDDP" is a description of an anti-wear additive, it tells us nothing of the actual sub-chemical composition. The nuiances really matter, as to the formation (or destruction) of the anti-wear layer.


Of course, getting the bulk of BITOGers to acknowledge this is difficult. And getting them to actually agree to it is nearly impossible. Regardless of how much proof (SAE study and Stark's example) one lays down. The oil bigotry runs deep here; long, wide and deep. Despite the facts.
Posted by: Garak

Re: UOA article - what is "normal" - 11/08/12 09:42 AM

Well, one thing about the old small blocks, you could throw all the ZDDP at them you wanted to, of whatever chemical makeup, and it would eat cams anyhow. wink

As for detergent packages, I suppose that's one reason why certain racing oils have little to no detergent and a boat load of zinc. As for me, I'd rather run an oil with some ZDDP (as opposed to some aero oil), but I'm not seeing the ZDDP levels of older oils with rose tinted glasses, either. The only "dated" oils I can think of that would have guaranteed high levels of ZDDP were some of the older spec dual rated HDEOs. For the rest, oil companies figured out long ago they could cut phosphorous from the oil and save some cash without API/ILSAC telling them to do so.
Posted by: Sam_Julier

Re: UOA article - what is "normal" - 11/30/12 09:37 AM

David, My sincere appreciation for your efforts in preparing this article. Would it be possible to post a pdf of this article? Printing from the home page of the site produces screened typeface which is difficult to read. Thank you.
Posted by: zerosoma

Re: UOA article - what is "normal" - 01/18/13 06:07 PM

So, barring any problems with the engine - and I KNOW each case is different, but just for the sake of a blanket statement, a guy could run a conventional out to typical synthetic oci's (~10k range) without much cause for concern, pending that his engine was in good shape and the oil was a name brand...?
Posted by: Stubb

Re: UOA article - what is "normal" - 02/19/13 01:18 PM

I am very interested in the "wear versus miles" analysis you performed, as a misunderstanding of this can be the basis for claims about oil quality and wear. From looking at your data presented, it seems that you could perform a regression analysis on your data to model the slope. This may provide a "wear rate" that is informative and distinguishing among oils or applications. This might also define an endpoint for an oil by identifying an inversion point on the slope. Further, examination of short-interval data across multiple changes (a paired analysis of data) may show an average initial rate due to tribochemical reaction with the new material. If this is truly wear (the metal has to come from somewhere) it would seem that a goal of lubricant design would be to reduce that initial wear rate.
Posted by: dustyroads

Re: UOA article - what is "normal" - 09/29/13 06:23 PM

I read your article late last year when I had just found this site and knew very little about the things we discuss on bitog. I just read it again and have much more appreciation for it now. I plan to make use of the info (the best I can), although I still have a lot to learn.

Thanks Dave !