UOA vs Teardown results
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The answer is:
Oil filters.
BTW, I'd rather do an oil change than get a used oil analysis.
Oil filters.
BTW, I'd rather do an oil change than get a used oil analysis.
Last edited:
Originally Posted By: mechtech2
The answer is:
Oil filters.
BTW, I'd rather do an oil change than get a used oil analysis.
+1 I'll save the cash, use a better oil and air filter, and change the oil earlier. It's worked for 35+ years. If I feel I have a problem then I might consider a used oil analysis if I can't detect an AF leak with the pressure tester, or fuel economy takes a hit for no reason. JMO
The answer is:
Oil filters.
BTW, I'd rather do an oil change than get a used oil analysis.
+1 I'll save the cash, use a better oil and air filter, and change the oil earlier. It's worked for 35+ years. If I feel I have a problem then I might consider a used oil analysis if I can't detect an AF leak with the pressure tester, or fuel economy takes a hit for no reason. JMO
BuickGN,
This recent thread covers your question:
https://bobistheoilguy.com/forums/threads/camshaft-lobe-wear.110976/
If one is serious about finding increased wear, one needs to do particle count AND weigh metal particles in oil filter. Cheap UOA may or may not show anything and could be misleading.
This recent thread covers your question:
https://bobistheoilguy.com/forums/threads/camshaft-lobe-wear.110976/
If one is serious about finding increased wear, one needs to do particle count AND weigh metal particles in oil filter. Cheap UOA may or may not show anything and could be misleading.
Use a Quality oil and quality oil filter and change at a reasonable interval and "hope for the best". I think this is all one can do!
Originally Posted By: maximus
I feel the value of used oil analysis is knowing how long to use oil. It can be considered a cost saving tool(over time). Frankly, I feel all oil is the same. Syns last longer. That's it lol. My supply of PP is running low. After it's gone, I'm going back to conventional oil.
How are regular used oil analysis going to save you money? At $30-40 per test, that is about double what I'd pay for an oil change (Motorcraft synthetic blend x 7qts and a Wix oil filter). I may do one just for giggles, but I'm not deluding myself that it is "saving me money".
I suspect the number of people on these forums (and on the planet) that could reliably head off an engine failure by divining UOA results is vanishingly small.
I feel the value of used oil analysis is knowing how long to use oil. It can be considered a cost saving tool(over time). Frankly, I feel all oil is the same. Syns last longer. That's it lol. My supply of PP is running low. After it's gone, I'm going back to conventional oil.
How are regular used oil analysis going to save you money? At $30-40 per test, that is about double what I'd pay for an oil change (Motorcraft synthetic blend x 7qts and a Wix oil filter). I may do one just for giggles, but I'm not deluding myself that it is "saving me money".
I suspect the number of people on these forums (and on the planet) that could reliably head off an engine failure by divining UOA results is vanishingly small.
Certainly used oil analysis are not without merit. Using them to measure the condition of the oil after X miles is certainly a valid and intelligent use of this tool. I would never have been convinced I could do a 10K mile OCI without seeing and then having a used oil analysis done on my own car.
There are a wealth of used oil analysis here on Bitog and I think that mass of evidence can be used to circumstantially judge the condition of your vehicle's engine. When you can pull up 4-10 used oil analysis on the same engine as your own and see where the wear rates fall, that tells you something about how these engines tend to spit metals. Copper in GM's newest V8s anyone?
BGN - You fail to mention if this car of yours was your daily driver or possibly something other than a factory, stock car. While that shouldn't change how a used oil analysis reads your oil, it certainly changed how you treated the vehicle and what it was used for. I think a used oil analysis might have less value for a vehicle that sees severe duty or one where we expect the wear to be greater.
Clark
There are a wealth of used oil analysis here on Bitog and I think that mass of evidence can be used to circumstantially judge the condition of your vehicle's engine. When you can pull up 4-10 used oil analysis on the same engine as your own and see where the wear rates fall, that tells you something about how these engines tend to spit metals. Copper in GM's newest V8s anyone?
BGN - You fail to mention if this car of yours was your daily driver or possibly something other than a factory, stock car. While that shouldn't change how a used oil analysis reads your oil, it certainly changed how you treated the vehicle and what it was used for. I think a used oil analysis might have less value for a vehicle that sees severe duty or one where we expect the wear to be greater.
Clark
Originally Posted By: Zaedock
Originally Posted By: BuickGN
I think we need this out in the open. I see people every day basing oil choice on used oil analysis wear metal results. We all know the benefits of used oil analysis for showing oil life remaining, coolant leaks, fuel dilution, etc. What I'm focusing on here is the common $30 used oil analysis and wear metal results.
My experience is they mean nothing whatsoever for determining wear rates.
Hey man, you know I agree with you on many subjects here at BITOG, but I'm going to have to disagree that used oil analysis are useless.
Besides being great to determine oil longevity, they can be helpful to monitor wear metals. I know in your case, it did nothing for you, but that's one engine in a world of millions.
I think you're lucky that you have the ability and time(plus, it's your hobby) to tear your engine down and check it out. Most everyone else are not able to, so a used oil analysis is the next best tool. Given the knowledge I've picked up here over the years and my personal drag racing and off road experience, I'll offer that used oil analysis can be helpful in most cases. Using my 2.5L trail Jeep as an example, the Fe levels have been in the single digits in a design that ofen has high iron. That's running Delo SAE30 of all things. Ultimately, what does it mean? Heck, no one really knows where the iron comes from. One thing I do know is that I feel a little better seeing 9PPM iron instead of 29 after a season of beatings. Although the next time I roll, the engine could fry anyway...
Many people buy things on recommendation and perceived performance, oil included. You have to admit that it's hard not to look at Utah Bill's used oil analysis and run out to get the oil he's using.
Nothing wrong with disagreeing.
I would put more weight on a used oil analysis if someone had an engine that consistantly showed high wear metals and eventually did a teardown and found actual wear taking place. To my knowlege, no one on this board has, though I haven't read through every used oil analysis.
I guess one of the biggest problems with the used oil analysis is if it looks good, the engine might be good, might be bad. If it looks bad, same conclusion.
Originally Posted By: BuickGN
I think we need this out in the open. I see people every day basing oil choice on used oil analysis wear metal results. We all know the benefits of used oil analysis for showing oil life remaining, coolant leaks, fuel dilution, etc. What I'm focusing on here is the common $30 used oil analysis and wear metal results.
My experience is they mean nothing whatsoever for determining wear rates.
Hey man, you know I agree with you on many subjects here at BITOG, but I'm going to have to disagree that used oil analysis are useless.
Besides being great to determine oil longevity, they can be helpful to monitor wear metals. I know in your case, it did nothing for you, but that's one engine in a world of millions.
I think you're lucky that you have the ability and time(plus, it's your hobby) to tear your engine down and check it out. Most everyone else are not able to, so a used oil analysis is the next best tool. Given the knowledge I've picked up here over the years and my personal drag racing and off road experience, I'll offer that used oil analysis can be helpful in most cases. Using my 2.5L trail Jeep as an example, the Fe levels have been in the single digits in a design that ofen has high iron. That's running Delo SAE30 of all things. Ultimately, what does it mean? Heck, no one really knows where the iron comes from. One thing I do know is that I feel a little better seeing 9PPM iron instead of 29 after a season of beatings. Although the next time I roll, the engine could fry anyway...
Many people buy things on recommendation and perceived performance, oil included. You have to admit that it's hard not to look at Utah Bill's used oil analysis and run out to get the oil he's using.
Nothing wrong with disagreeing.
I would put more weight on a used oil analysis if someone had an engine that consistantly showed high wear metals and eventually did a teardown and found actual wear taking place. To my knowlege, no one on this board has, though I haven't read through every used oil analysis.
I guess one of the biggest problems with the used oil analysis is if it looks good, the engine might be good, might be bad. If it looks bad, same conclusion.
Originally Posted By: ClarkB
BGN - You fail to mention if this car of yours was your daily driver or possibly something other than a factory, stock car. While that shouldn't change how a used oil analysis reads your oil, it certainly changed how you treated the vehicle and what it was used for. I think a used oil analysis might have less value for a vehicle that sees severe duty or one where we expect the wear to be greater.
Clark
At that point it was a daily driver. I had no dyno back then but it ran a best time of 10.60 so I would guess aound 500hp at the wheels, close to 600 at the crank. I used it for commuting 210 miles round trip to work for it's last few months. I was always worried about it leaving me stranded so I did used oil analysis pretty often. Still went to the track once a month or so, played around on the street a little too. I'm pretty sure I know what started the massive wear and if used oil analysis worked I would have a clear cut answer. I like to determine the cause of failure and unfortunately I wasn't able to this time.
BGN - You fail to mention if this car of yours was your daily driver or possibly something other than a factory, stock car. While that shouldn't change how a used oil analysis reads your oil, it certainly changed how you treated the vehicle and what it was used for. I think a used oil analysis might have less value for a vehicle that sees severe duty or one where we expect the wear to be greater.
Clark
At that point it was a daily driver. I had no dyno back then but it ran a best time of 10.60 so I would guess aound 500hp at the wheels, close to 600 at the crank. I used it for commuting 210 miles round trip to work for it's last few months. I was always worried about it leaving me stranded so I did used oil analysis pretty often. Still went to the track once a month or so, played around on the street a little too. I'm pretty sure I know what started the massive wear and if used oil analysis worked I would have a clear cut answer. I like to determine the cause of failure and unfortunately I wasn't able to this time.
Originally Posted By: JAG
used oil analysis wear metals only measure particles small enough to be measured and the particles need to make it into the oil sample bottle. Different particle size ranges do occur with different oils, different engines, different driving styles, different dirt contamination, etc. Different sampling methods can also affect the particle sizes captured as well as the concentration of them. Different particle sizes affect how likely they end up in the oil sample bottle.
So there are many pathways for the results to be underestimated (relative to true concentration). If comparing one result that had less underestimation to one that had more underestimation, that one result will appear elevated.
But if you hold as many variables nearly constant (including the specific oil used and having used it long enough for stabilization to occur) and do several used oil analysis back to back, trending can generally allow decent conclusions to be made.
I say generally because there is still the possibility of severe wear occurring and the particles are so large, that the used oil analysis results greatly underestimate the true wear rate. If severity of wear goes up from there the results will be an even greater underestimation and it will be hard or impossible for the used oil analysis reader to catch it. This situation is not common but it does happen to those unlucky enough to be in it...like BuickGN was. It's also happened in VW 2.0T engines where severe wear has occurred in certain parts of the valvetrain.
Since different oils generally produce different wear particle size distributions, I think it is generally unwise to say that based on a set of used oil analysis, one oil is causing less wear than another. Again I say "generally" but not always.
Adding a PQ Index test to a standard used oil analysis, as Gary mentioned, greatly helps get a better estimation of true iron wear rate. But that still is based on what's in the oil sample bottle so that needs to be as representative as possible the ideal: the entire oil in the engine with all iron/steel wear particles homogeneously mixed in it.
I agree with this. Considering the engine went from new to completely trashed in less than 10,000 miles, it's likely my wear particles were larger than normal. But wouldn't you think that there would be SOME smaller particles? Even if it came from the larger ones getting ground together.
used oil analysis wear metals only measure particles small enough to be measured and the particles need to make it into the oil sample bottle. Different particle size ranges do occur with different oils, different engines, different driving styles, different dirt contamination, etc. Different sampling methods can also affect the particle sizes captured as well as the concentration of them. Different particle sizes affect how likely they end up in the oil sample bottle.
So there are many pathways for the results to be underestimated (relative to true concentration). If comparing one result that had less underestimation to one that had more underestimation, that one result will appear elevated.
But if you hold as many variables nearly constant (including the specific oil used and having used it long enough for stabilization to occur) and do several used oil analysis back to back, trending can generally allow decent conclusions to be made.
I say generally because there is still the possibility of severe wear occurring and the particles are so large, that the used oil analysis results greatly underestimate the true wear rate. If severity of wear goes up from there the results will be an even greater underestimation and it will be hard or impossible for the used oil analysis reader to catch it. This situation is not common but it does happen to those unlucky enough to be in it...like BuickGN was. It's also happened in VW 2.0T engines where severe wear has occurred in certain parts of the valvetrain.
Since different oils generally produce different wear particle size distributions, I think it is generally unwise to say that based on a set of used oil analysis, one oil is causing less wear than another. Again I say "generally" but not always.
Adding a PQ Index test to a standard used oil analysis, as Gary mentioned, greatly helps get a better estimation of true iron wear rate. But that still is based on what's in the oil sample bottle so that needs to be as representative as possible the ideal: the entire oil in the engine with all iron/steel wear particles homogeneously mixed in it.
I agree with this. Considering the engine went from new to completely trashed in less than 10,000 miles, it's likely my wear particles were larger than normal. But wouldn't you think that there would be SOME smaller particles? Even if it came from the larger ones getting ground together.
Originally Posted By: ekpolk
Originally Posted By: pbm
I agree with BuickGN and I would rather spend my money changing my oil than having a used oil analysis done. I did have a used oil analysis done once to see if my GM 3.1 was leaking coolant into my oil.
Unstated, and faulty premise: you can only change oil OR do used oil analysis. I prefer to do BOTH. My engine has fresh, clean oil just like yours, AND I know much more about the condition of my oil, and YES, of my engine too (but again, certainly NOT perfect knowledge).
Here's what I don't get. I get attacked for spending $10/quart on Redline. Yet it's ok to tack $30 on to an oil change for a used oil analysis every time? Not really aimed at you but those who think I'm retarded for spending the money I do. Unless I'm pushing the absolute limits of an OCI, I would rather spend extra money on a premium oil and call it good.
Originally Posted By: pbm
I agree with BuickGN and I would rather spend my money changing my oil than having a used oil analysis done. I did have a used oil analysis done once to see if my GM 3.1 was leaking coolant into my oil.
Unstated, and faulty premise: you can only change oil OR do used oil analysis. I prefer to do BOTH. My engine has fresh, clean oil just like yours, AND I know much more about the condition of my oil, and YES, of my engine too (but again, certainly NOT perfect knowledge).
Here's what I don't get. I get attacked for spending $10/quart on Redline. Yet it's ok to tack $30 on to an oil change for a used oil analysis every time? Not really aimed at you but those who think I'm retarded for spending the money I do. Unless I'm pushing the absolute limits of an OCI, I would rather spend extra money on a premium oil and call it good.
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Quote:
So, to sum up, my specific disagreement with this premise is that you simply take it too far.
BGN can't separate from himself and see that he's a empirical data point of one. He's never going to be able to remove himself from that position. It's totally understandable. The unheralded elephant in the room is those used oil analysis that would show all wear indicators in step with wear.
Have we actually seen BGN's used oil analysis for peer review? I think he said that they weren't pretty, but acceptable in his view.
..but there's no denying that he was sucker punched with his perception of acceptable were indicators vs. the real wear impact.
So, to sum up, my specific disagreement with this premise is that you simply take it too far.
BGN can't separate from himself and see that he's a empirical data point of one. He's never going to be able to remove himself from that position. It's totally understandable. The unheralded elephant in the room is those used oil analysis that would show all wear indicators in step with wear.
Have we actually seen BGN's used oil analysis for peer review? I think he said that they weren't pretty, but acceptable in his view.
..but there's no denying that he was sucker punched with his perception of acceptable were indicators vs. the real wear impact.
Originally Posted By: Gary Allan
Quote:
So, to sum up, my specific disagreement with this premise is that you simply take it too far.
BGN can't separate from himself and see that he's a empirical data point of one. He's never going to be able to remove himself from that position. It's totally understandable. The unheralded elephant in the room is those used oil analysis that would show all wear indicators in step with wear.
Have we actually seen BGN's used oil analysis for peer review? I think he said that they weren't pretty, but acceptable in his view.
..but there's no denying that he was sucker punched with his perception of acceptable were indicators vs. the real wear impact.
I'm fully aware of what it is or isn't. I'm one data point however I had 4-5 used oil analysis on the failing engine. You may question my intelligence if I continue to put faith in used oil analysis. Mine are long gone, they were done years before I was on this site but I had nothing in the double digits. Copper showed up where there was none before.
Quote:
So, to sum up, my specific disagreement with this premise is that you simply take it too far.
BGN can't separate from himself and see that he's a empirical data point of one. He's never going to be able to remove himself from that position. It's totally understandable. The unheralded elephant in the room is those used oil analysis that would show all wear indicators in step with wear.
Have we actually seen BGN's used oil analysis for peer review? I think he said that they weren't pretty, but acceptable in his view.
..but there's no denying that he was sucker punched with his perception of acceptable were indicators vs. the real wear impact.
I'm fully aware of what it is or isn't. I'm one data point however I had 4-5 used oil analysis on the failing engine. You may question my intelligence if I continue to put faith in used oil analysis. Mine are long gone, they were done years before I was on this site but I had nothing in the double digits. Copper showed up where there was none before.
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You've just experienced a VERY BIG "NEVER AGAIN!" event. That's all. It happened to YOU. Once bitten ..you can never see it too many other ways.
If I had something like that happen to me, I really don't think I could react any other way either. Beliefs/faiths/paradigms are destroyed and formed in this manner all the time.
The Cu was surely there when the Pb was gone.
Originally Posted By: BuickGN
. . .
Here's what I don't get. I get attacked for spending $10/quart on Redline. Yet it's ok to tack $30 on to an oil change for a used oil analysis every time? Not really aimed at you but those who think I'm retarded for spending the money I do. Unless I'm pushing the absolute limits of an OCI, I would rather spend extra money on a premium oil and call it good.
Not by me, you don't! I had been planning to order up some RL myself after I used up my little stash of Pennzoil Platinum 0w20. Then came the M1 special, whereby I ended up with a bunch of ~$3.50-ish M1. So, when I use THAT up (assuming no more sale distractions), I'll be right with you in trying RL. I'd rather just admit I'm a car and car care junkie, and spend the money to do both.
. . .
Here's what I don't get. I get attacked for spending $10/quart on Redline. Yet it's ok to tack $30 on to an oil change for a used oil analysis every time? Not really aimed at you but those who think I'm retarded for spending the money I do. Unless I'm pushing the absolute limits of an OCI, I would rather spend extra money on a premium oil and call it good.
Not by me, you don't! I had been planning to order up some RL myself after I used up my little stash of Pennzoil Platinum 0w20. Then came the M1 special, whereby I ended up with a bunch of ~$3.50-ish M1. So, when I use THAT up (assuming no more sale distractions), I'll be right with you in trying RL. I'd rather just admit I'm a car and car care junkie, and spend the money to do both.
Originally Posted By: ekpolk
Originally Posted By: BuickGN
. . .
Here's what I don't get. I get attacked for spending $10/quart on Redline. Yet it's ok to tack $30 on to an oil change for a used oil analysis every time? Not really aimed at you but those who think I'm retarded for spending the money I do. Unless I'm pushing the absolute limits of an OCI, I would rather spend extra money on a premium oil and call it good.
Not by me, you don't! I had been planning to order up some RL myself after I used up my little stash of Pennzoil Platinum 0w20. Then came the M1 special, whereby I ended up with a bunch of ~$3.50-ish M1. So, when I use THAT up (assuming no more sale distractions), I'll be right with you in trying RL. I'd rather just admit I'm a car and car care junkie, and spend the money to do both.
Thank you. I wouldn't mind doing used oil analysis on the RL the first time or two just to satisfy my own curiosity but that's starting to push the limits of my budget.
Originally Posted By: BuickGN
. . .
Here's what I don't get. I get attacked for spending $10/quart on Redline. Yet it's ok to tack $30 on to an oil change for a used oil analysis every time? Not really aimed at you but those who think I'm retarded for spending the money I do. Unless I'm pushing the absolute limits of an OCI, I would rather spend extra money on a premium oil and call it good.
Not by me, you don't! I had been planning to order up some RL myself after I used up my little stash of Pennzoil Platinum 0w20. Then came the M1 special, whereby I ended up with a bunch of ~$3.50-ish M1. So, when I use THAT up (assuming no more sale distractions), I'll be right with you in trying RL. I'd rather just admit I'm a car and car care junkie, and spend the money to do both.
Thank you. I wouldn't mind doing used oil analysis on the RL the first time or two just to satisfy my own curiosity but that's starting to push the limits of my budget.
Originally Posted By: Gary Allan
Not at all BGN!! NO. This isn't a slam! Not AT ALL.
You've just experienced a VERY BIG "NEVER AGAIN!" event. That's all. It happened to YOU. Once bitten ..you can never see it too many other ways.
If I had something like that happen to me, I really don't think I could react any other way either. Beliefs/faiths/paradigms are destroyed and formed in this manner all the time.
The Cu was surely there when the Pb was gone.
Ha ha. I'm still open if others can prove something different to me.
I've always had lead near the double digits, I assumed it was from the lead in the gas, maybe it was the early signs of the bearings going away.
You've just experienced a VERY BIG "NEVER AGAIN!" event. That's all. It happened to YOU. Once bitten ..you can never see it too many other ways.
If I had something like that happen to me, I really don't think I could react any other way either. Beliefs/faiths/paradigms are destroyed and formed in this manner all the time.
The Cu was surely there when the Pb was gone.
Ha ha. I'm still open if others can prove something different to me.
I've always had lead near the double digits, I assumed it was from the lead in the gas, maybe it was the early signs of the bearings going away.
Even if you had a used oil analysis trend and that trend showed an increase in lead, copper etc the truth is, would you tear down that engine and rebuild it or trade the vehicle etc. Honestly now, tell the wife hey, we need to dump this car or put in a rebuilt because I am certain the engine is due for failure soon based upon increasingly disturbing wear metal results in my used oil analysis! That would really go over well so the answer is--- In all probability, NO. I had this scenerio on one Vehicle, I believe even Terry thought I was headed for a catastrophic failure, but that engine lasted 3 more years and traded it still running.
I have spent a small fortune on used oil analysis, I did this for about 10 years then evaluated the results and said, guess what, not only does it not make any difference, but I concluded that even if I saw a terrible trend I would do nothing anyway (other then a coolant leak ) so why bother tormenting myself and wasting the money!
I have spent a small fortune on used oil analysis, I did this for about 10 years then evaluated the results and said, guess what, not only does it not make any difference, but I concluded that even if I saw a terrible trend I would do nothing anyway (other then a coolant leak ) so why bother tormenting myself and wasting the money!
Originally Posted By: Spector
Even if you had a used oil analysis trend and that trend showed an increase in lead, copper etc the truth is, would you tear down that engine and rebuild it or trade the vehicle etc. Honestly now, tell the wife hey, we need to dump this car or put in a rebuilt because I am certain the engine is due for failure soon based upon increasingly disturbing wear metal results in my used oil analysis! That would really go over well so the answer is--- In all probability, NO. I had this scenerio on one Vehicle, I believe even Terry thought I was headed for a catastrophic failure, but that engine lasted 3 more years and traded it still running.
I have spent a small fortune on used oil analysis, I did this for about 10 years then evaluated the results and said, guess what, not only does it not make any difference, but I concluded that even if I saw a terrible trend I would do nothing anyway (other then a coolant leak ) so why bother tormenting myself and wasting the money!
You just lost interest. Teardown, trade, or throw rocks at it -- at least you know that some action is probably warranted. You are now, in essence, taking the position that you're more comfortable with your head (engine?) in the sand. I would rather know. And I WOULD act, one way or the other, if I thought I saw bad things coming. Of course, the first "acting" would be looking for corroborating information before taking drastic action. Hey, it's a free country (mostly), and it's your money (sort of). Do what makes you most comfortable.
Even if you had a used oil analysis trend and that trend showed an increase in lead, copper etc the truth is, would you tear down that engine and rebuild it or trade the vehicle etc. Honestly now, tell the wife hey, we need to dump this car or put in a rebuilt because I am certain the engine is due for failure soon based upon increasingly disturbing wear metal results in my used oil analysis! That would really go over well so the answer is--- In all probability, NO. I had this scenerio on one Vehicle, I believe even Terry thought I was headed for a catastrophic failure, but that engine lasted 3 more years and traded it still running.
I have spent a small fortune on used oil analysis, I did this for about 10 years then evaluated the results and said, guess what, not only does it not make any difference, but I concluded that even if I saw a terrible trend I would do nothing anyway (other then a coolant leak ) so why bother tormenting myself and wasting the money!
You just lost interest. Teardown, trade, or throw rocks at it -- at least you know that some action is probably warranted. You are now, in essence, taking the position that you're more comfortable with your head (engine?) in the sand. I would rather know. And I WOULD act, one way or the other, if I thought I saw bad things coming. Of course, the first "acting" would be looking for corroborating information before taking drastic action. Hey, it's a free country (mostly), and it's your money (sort of). Do what makes you most comfortable.
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