Dirt or Wear?

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34,044
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Southern NJ
Does anyone other then myself and msparks think we over-analyze UOA reports? I think I read somewhere, and this is very much just common sense, that dirt is your engine's biggest enemy. Take this scenario, if you have sampled two oils under the same conditions and lets say one oil gave you copper, iron and lead numbers that were 6-12ppm higher for a given interval, do you think it will make that much of a difference down the road if this trend remained FAIRLY consistant? I really think that unless you plan on driving the same car well over 250k miles, it might not really make that much of a difference. I'm sure compression will be somewhat better, but keeping the engine clean, another benefit of synthetics, will be more crucial then worrying about ppm. [ September 09, 2003, 06:18 PM: Message edited by: buster ]
 

Patman

Staff member
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Oakville, Ontario
We probably do overanalyze things, but then again, if we didn't, what else would we do on here? [Smile] Seriously though, I often wonder, if I have UOAs which show a consistent 3ppm/1000 mile wear pattern for iron and lead, exactly what kind of engine life would I get? I strive to get my wear down to 1 or 1.5ppm/1000 miles, but it could end up being overkill if 3ppm/1000 miles still gets me 250k out of my engine.
 
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1,759
Location
Elizabeth City NC
I think the two are related. A clean engine will show less ware numbers. Less ware numbers are an indication of a clean engine. We see this with auto-rx. After treatment numbers are always better than before treatment numbers. I do drive cars up to and beyond the 250,000 mile figure so all this is important to me. If I had some of the knowlege from this site when my Toyota was new it would have less oil consumption than it does at 250,000. At least that is what I believe. 15 years from now I will know as my new car will have that many miles and I can compare. I already know this to be true from other users on this site that have used better oils than I have.
 

Al

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Elizabethtown, Pa
I guess none of know how much wear will lead to a loss or gain in expected life of an engine. I remember reading an article in an SAE Publication where Mobil ran an "Aunt Minnie" test where a vehicle was driven 6 years without an oil change with very very short trips. No warmup in that period of time. Now there was replacement oil when they sampled. Towards the end they were getting in the 400 to 500 ppm range in iron. When they tore down the engine they were unable to determine where all of iron was coming from. Go figure. I'm sure we are over-reacting to wear numbers. But as Patman said We probably do overanalyze things, but then again, if we didn't, what else would we do on here? [Smile] [ September 09, 2003, 08:08 PM: Message edited by: Al ]
 
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5,358
Location
Gone
If we are going to do UOAs anyway to ensure everything is OK internally and since we are a bunch of oil nuts (well, some of us anyway), why not attempt to fine tune the results with analysis and adjustment (oil brands, viscosities, etc) as well? Listen to sports radio and tell me we are worse than all the wannabe coaches and team managers out there in radio land (and those guys can't even affect the outcomes of the teams and situations they analyze to death).
 

buster

Thread starter
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34,044
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Southern NJ
I agree and am all for doing UOA's. I just wanted to see what everyone thought of the significance of them. [Cheers!]
 
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Ocala, Florida
Based on my continued analysis, I've made changes and have seen it reflect in each analysis. So, yes, it can make a difference. I've managed to lower my wear numbers considerably by tweaking on different things. No telling for sure, but expect to do maybe a little bit more tweaking. Not only is this benificial to the engine, it helps keep the engine running at peak as it shows me time for a tune up and air filter change.
 
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3,327
Location
Bolivia
Probably most people on this board go overboard trying to get the wear numbers to the very minimum. At some point there are diminishing returns. But for many people I've gotten iron from 200ppm+ in 2000 km to 20 ppm in 10,000 km. And similar results for the rest of the wear metals. For one person with 180 engines we used analisis to get from 90 ppm in 200 hours to 25 in 500 hours between changes. Those changes are dramatic. I believe once the numbers are in the 10,2,2 type range at 6,000 km or 400 hours, the rest of the fine tuning is great but may cost more than the final benefit.
 
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Falls Church VA
Overanalyzing? Overreacting? Seems that I recall many, many moons ago, that the margin of error in the spectroscopic analysis is somewhere in the plus/minus 40% area. So getting 1 reading at 10 ppm and the next at 15 ppm probably isn't a sign of anything serious enough to panic. Now, a series of checks which shows sudden increase in specific wear metals can mean something. Think of it guys--the lab is detecting what amounts to a shot of vermouth in a swimming pool full of gin!
 

Patman

Staff member
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Oakville, Ontario
quote:
Originally posted by Dick in Falls Church: Overanalyzing? Overreacting? Seems that I recall many, many moons ago, that the margin of error in the spectroscopic analysis is somewhere in the plus/minus 40% area. So getting 1 reading at 10 ppm and the next at 15 ppm probably isn't a sign of anything serious enough to panic. Now, a series of checks which shows sudden increase in specific wear metals can mean something. Think of it guys--the lab is detecting what amounts to a shot of vermouth in a swimming pool full of gin!
I think that most labs are way more consistent than that nowadays though. Just look at 3MPs long term test. It looks to me like Blackstone is extremely accurate, otherwise we'd be seeing the wear metals shifting all over the place, but instead they are going up ever so slightly on each 1000 mile interval. I'd venture to say that their accuracy is to within plus or minus 1ppm! I'm not joking.
 
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Gone
quote:
Originally posted by Dick in Falls Church: Think of it guys--the lab is detecting what amounts to a shot of vermouth in a swimming pool full of gin!
No germs living in that pool, for sure! [Wink]
 
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