anyone have a UOA that the lab said the oil was actually due for a change?
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dnewton3
Staff member
Due to character limits, I'll have to address my answer in two parts ... Two replies, as it were, from one answer.
My apologies if I misunderstood your initial comment I quoted; I took it as an inference that you thought UOAs were essentially not a good predictor of when to do something for a major maintenance event.
I'll defend what I claimed, but perhaps it's not germane to what your intent was. So for that I again apologize.
UOAs are not perfect; if we can agree on that, it's a good starting point.
But UOAs are most certainly useful tools which can impart information that is helpful, very much so, to understanding wear in both normal and abnormal senses.
First I'll speak to when things go badly:
As for macro events of impending catastrophe, there are plenty of anecdotal stories well documented where UOAs didn't pick up on the looming doom, and bad things occurred. But there are also plenty of anecdotal stories where UOAs did in fact pick up wear metal trends that ended up being a engine-life-saving (or at least life-altering) tid-bit which saved an engine from demise because the UOA showed a wear trend far outside of the "norm", and that alert was heeded, led to mechanical repair rather than mechanical demise; plenty of Blackstone examples in their newletters.
and the list can go on ...
What I would offer here is that UOAs will never catch every single issue, for a variety of reasons. But they most certainly do have the ability to detect things going wrong which, if caught soon enough, can lead to a major mechanical maintenance decision that might save money. If you don't agree, then we'll have to agree to disagree. I've seen so many examples of this type of "salvation" that it cannot be ignored or denied; UOAs can provide good information which leads to a proper mechanical decision being made.
Now I'll speak to when things go well:
UOAs can be used as a confirmation that wear is well in order, and equipment is in good shape, and maintenance efforts can be deferred (typically interpreted as an OCI extension). The purpose of oil is not to exist for itself; it's there to reduce wear. All things that oil does (lubricate, clean, cool) are inputs to the desire output; that of wear reduction. There are a bazillion examples of lubes doing a great job at this; countless UOAs which confirm that wear rates in a piece of equipment are well in line.
here's a condensed version of my point: https://www.machinerylubrication.com/Read/30383/engines-oil-analysis
Using OAs to track lube health is OK, but it's only giving a prediction of when things might go wrong. But using OA to track trends in wear metals not only will likely indicate a potential wear-related failure, but also help narrow the focus as to what you might be looking for (Pb, Cu, Fe, Cr, Al can all give indication as to what component(s) might be failing). There is no ability of FP, vis, soot or fuel which will tell you what component is at risk, but the metals surely will! In other words, UOAs give us a two-pronged approach to understanding the overall symbiotic relationship between lube and equipment. UOAs will tell us the direct health of the lube, but that is only an indication that something might go wrong in the future (vis gets too thin; FP way high from excess fuel; soot too high) all simply imply that wear is likely to escalate soon. But if you see a trend in metals shifting, that's the actual evidence that the event is occurring!
Side bar - we'll probably agree that no OA is ever going to discern an acute failure; it's not going to discern a con-rod snapping from over-rev conditions, or a block cracking from thermal stress, etc ... UOAs are good at tracking chronic issues; those which develop over time. This is both a benefit and a limitation of the tool, and speaks to what I was illuminating in my initial comment about how/why to use UOAs, and what they can and cannot tell us.
There is a very interesting article by Fleetguard called "Differentiating Filter Performance by Oil Analysis Results". At face value, it would seem to prove that UOAs won't track the differences in filter efficiency and therefore a knee-jerk reaction is to assume that UOAs are not of value. But that totally misses a very fundamental concept ... The presumption is that there is a wear differential occurring and the UOA is missing it. Did it ever occur to the authors that the reason there's no ability to differentiate filter efficiency is because the physical differences in filters is not able to manifest into a wear differential in the first place? In other words, what the UOA data is telling them is that the effect of filtration is moot at certain OCI intervals. Their presumption is flawed; they believe the UOA is missing (not detecting) a difference, when the reality is that the UOA is telling them there exists no difference, when it comes to the filtration chosen combined with the OCI interval selected. This is just one example of misleading conclusions which taint people's view of UOAs.
SAE 2000-01-0234 (which I often refer to as the bus-study) shows a good correlation between PCs (particulate counts) and UOA wear date (Fe wear). They track many attributes of the lube, and show a good relationship between engine wear and contamination. It's an older study, and has lost some of it's relevance due to outdated engine designs, but it's a good example of how wear is easily tracked in UOAs.
SAE 2007-01-4133 shows how wear rates actually decline over fairly long OCIs. There is typically an elevated wear rate at the front end of an OCI, then it slowly drops as the miles pile up and the wear stays near-steady; effectively resulting in a declining wear rate. They use multiple methods of wear analysis (proton bombardment; electron spectroscopy; infrared reflection absorption). These are very finite, lab-intensive tests which the average BITOGer will not have cost-effective access to. But UOAs are very affordable, and they echo the exact same story for most all applications. The "normalcy" article I linked above clearly shows how UOAs repeatedly confirm that wear metals in UOAs exhibit the exact same phenomenon (that of wear escalation at the front end of an OCI, and subsequent deescalation across longer OCIs) as did the very expensive other methodologies. It's pretty hard to ignore what amounts to (literally) tens of thousands of UOAs showing the exact same effect in wear metal data. I guess one can choose to ignore the facts, but I accept them for what they are. UOAs are a reliable means to track wear which is shown to exhibit the exact same trends using far different equipment for analysis. In short, different methods of tracking wear come to the same conclusions; not by accident by by convergence of conclusions. While I would agree that UOAs have not been proven to be as accurate, they most certainly do exhibit a high degree of sensitivity tracking "normal" wear; completely echoing the other more expensive methods of doing so.
continued in next post ...
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dnewton3
Staff member
SAE 881825 (the infamous GM filter study) would first lead people to some conclusions which I find difficult to swallow. But ... (and this is germane to my overall point), they do show that UOA wear metal data tracks in concert with particulate size and quantity. IOW, the wear metals in the UOA are a result of the contamination levels in the lube. They used not only PCs, but physical component weight inspections prior to and after the test. Relative wear rates were also collected via spectro-chemical analysis. Bottom line is that the induction of contamination (and using PC tracking), along with weight analysis before/after tests, and UOAs all showed correlation. The UOAs were able to track wear as the induction of particulate was introduced, and subsequently manipulated with filtration efficiency changes. I'm not a huge fan of this study, but it does again show that UOAs can track metal wear in a piece of equipment.
SAE 902238 (the older bus study) is also a study which focuses on filtration's effect of wear. And yet again, there is very good correlation between the wear metals tracked and the filtration efficiency which was manipulated. In short, the input variable (filter efficiency) was able to be discerned via the output (wear metals in UOAs). Whereas old city buses running 2-stroke diesel engines probably don't translate well into today's world (given clean running direct-injection gas and diesel engines today), the take-away is that UOAs are a good echo of other means of tracking wear induction.
SAE 952557 is an interesting study by Donaldson; their "Total Filtration" study. Some pretty good data in here. They realize (and take the approach) that reducing engine wear is not the sole job of any one attribute; that fuel, lube, and air filtration all contribute (along with other oil charactistics) to reducing wear. I quote the following: "The relative extent of engine wear determined by oil analysis or direct methods also equally effects the lube oil economy." The statement made here is that UOAs are used as one tool of many to track wear, and how that relates to filtration effects.
I will agree and emphatically state that UOAs are not a panacea of perfection; they have limitations and concerns. But they ARE accurate enough to be used in determining wear rates, as well as discerning some modes of equipment failure. They ARE a tool which can be used to make conclusions about mechanical conditions of equipment and the subsequent decisions regarding the maintenance thereof.
If you don't see it that way, that's fine. I do see it that way. I ran PM maintenance programs at the Ford facility I worked at for over a decade. I used a whole host of tools (UOAs, PCs, thermal analysis, vibration analysis) to track performance of all manner of equipment, and thereby develop a sound and successful maintenance program of said equipment.
Now, if I have misunderstood what your claim was, then I again owe you an apology. But I perceived that you were stating that UOAs are not a good means to measure equipment health, and I patently disagree with that, if that was your intended mantra.
SAE 902238 (the older bus study) is also a study which focuses on filtration's effect of wear. And yet again, there is very good correlation between the wear metals tracked and the filtration efficiency which was manipulated. In short, the input variable (filter efficiency) was able to be discerned via the output (wear metals in UOAs). Whereas old city buses running 2-stroke diesel engines probably don't translate well into today's world (given clean running direct-injection gas and diesel engines today), the take-away is that UOAs are a good echo of other means of tracking wear induction.
SAE 952557 is an interesting study by Donaldson; their "Total Filtration" study. Some pretty good data in here. They realize (and take the approach) that reducing engine wear is not the sole job of any one attribute; that fuel, lube, and air filtration all contribute (along with other oil charactistics) to reducing wear. I quote the following: "The relative extent of engine wear determined by oil analysis or direct methods also equally effects the lube oil economy." The statement made here is that UOAs are used as one tool of many to track wear, and how that relates to filtration effects.
I will agree and emphatically state that UOAs are not a panacea of perfection; they have limitations and concerns. But they ARE accurate enough to be used in determining wear rates, as well as discerning some modes of equipment failure. They ARE a tool which can be used to make conclusions about mechanical conditions of equipment and the subsequent decisions regarding the maintenance thereof.
If you don't see it that way, that's fine. I do see it that way. I ran PM maintenance programs at the Ford facility I worked at for over a decade. I used a whole host of tools (UOAs, PCs, thermal analysis, vibration analysis) to track performance of all manner of equipment, and thereby develop a sound and successful maintenance program of said equipment.
Now, if I have misunderstood what your claim was, then I again owe you an apology. But I perceived that you were stating that UOAs are not a good means to measure equipment health, and I patently disagree with that, if that was your intended mantra.
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I think there is a mutual semantics/grammar/phraseology mismatch here more than anything else because I don't see any significant differences between the essence of the points raised.
Thank you for the clarification and I will work to be more clear myself
Thank you for the clarification and I will work to be more clear myself
4WD
$50 site donor 2024
Same … we take samples from an active loop (no sump dumps) under load/temp and send to CAT … this is to validate that the lube is holding up as part of warranty etc. ”Top jobs” and full overhauling will still happen at the same hours since all predicted and we have to keep the engines at a prescriptive load … and the engines are computer monitored anyway (that’s why you have a number of engines to bring on/off) …
The cost of a V16 vs a drum of 15w40 ? Just not going to extend based on UOA
For me to pay for an UOA for my Jeep ? Could just go buy a jug of oil …
(and keep reading them here) …
It's effective at spotting a leaky injector or headgasket before it results in a $14,000 overhaul. It also has spotted rod/main bearing wearing into the next layer and needing replacement and bull gear bearings going before major damage. It's also allowed us to extend OCI from 15,000 mi to 40,000 mi with no decrease in miles before overhaul and buy a 10% cheaper lubricant and run the same filters for 40,000 mi instead of 20,000 mi.
All of that makes a difference when the engines take 41 Quarts.
I don't often use it on automobiles.
The primary issue is people here don't always use it correctly. If the analysis shows coolant don't shorten the drain Interval, find it and fix it! If analysis shows a lube is still good at 10,000 mi why are you changing it? If you are going to do 5,000 mi OCI regardless buy the cheapest oil that meets spec then do a UOA to prove it is actually what it's supposed to be and still good and forget it.
Not everyone agrees with me but I believe an oil with a less robust additive package does less initial "stripping". Using an excessive additive package and short drain intervals is not the ideal situation. This is why analysis often looks better on a standard conventional than a premium synthetic when both are changed at 3,000 mi. Contrary to what is often stated here studies have been done that showed the least measurable parts wear with a premium synthetic but to get it you had to run it the full drain Interval.
PS The 40,000 mi OCI I quoted above was with a conventional. 60,000 mi Synthetic was not cost effective given we still had to do 20,000 mi chassis service and the filters couldn't make 60,000 mi.
First time I've ever heard of UOA was after joining bitog. The elite group of people who care about their engines ...
I don't mean that in a bad way and understand since I myself am a little on the OCD side. My wife disagrees and thinks it's more than a little. lol
I have few friend and we do talk car (lots of oil talk) and over the years, know a few good local mechanics (not dealer) that the family and friends use and we've talked oil many times and never heard any of them mention uoa.
Maybe I will slowly get brainwashed and do one for fun. But I read that one uoa is not enough and I need to do it every oil change and "pattern" ... That was kind of a deal breaker for me but enjoy reading others.
I don't mean that in a bad way and understand since I myself am a little on the OCD side. My wife disagrees and thinks it's more than a little. lol
I have few friend and we do talk car (lots of oil talk) and over the years, know a few good local mechanics (not dealer) that the family and friends use and we've talked oil many times and never heard any of them mention uoa.
Maybe I will slowly get brainwashed and do one for fun. But I read that one uoa is not enough and I need to do it every oil change and "pattern" ... That was kind of a deal breaker for me but enjoy reading others.
I did. Blackstone told me to change.
I ran Motorcraft semi Synthetic 5w-20 9.2k on my 3.7L Ford. (Ford Quicklane oil change.) It was kind of an experiment. Only 6% life remaining as per IOLM.
Good wear numbers, but the oil was just about shot; the IOLM was dead bang accurate.
I agree with Gene. Not much point in a 5k UOA.
That is correct and even then the quality of the sample determines if the results are relative.
That being said, an OA does have and bring value as part of a comprehensive PM and asset management plan.
As a "stand alone" indicator of anything- not so much
Depends really on how you personally define "value" and what you intend to do with the OA results.
Yes, one just posted with Supertech. Blackstone recommended shortening to 10k.
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