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Nov 17, 2002
I often see persons quoting UOA as a determining factor in some opinions.

How can one form an opinion with one of two UOA or several all from different vehicles. One would it would take many miles to form such opinions. I am not referring to any one post or person in particular but I often here mentioned that based on UOA they determine an oil is not as good as some other.

I think many put to much reliability in these and there may no no trend there whatsoever. Its like saying I am not going to Disneyland anymore because it rained the last 2 times I was there.

Just my observations......
True, basing a decision on other people's UOAs isn't the best move, but if you look at a bunch of them it can show you a trend, such as if a certain oil thins out a lot, or shows higher than average wear, or if it's TBN drops faster.

The best way to determine things is to test it out yourself and do UOAs on your own vehicle, under your own driving conditions and climate. And not to jump to conclusions after just one UOA, but to do a few of them before deciding if an oil is worthwhile or not.

It's not perfect, but using other people's UOAs is certainly better than simply going by a bunch of literature put out by the oil company, or a commercial on TV or the opinion of a single person in your car club, etc.
There are a lot of variables that are possible. I am saying people look at the ones posted and form opinions, right or wrong and won't listen to reason.

I am saying the UOA from one vehicle may not even be remotely pertinent to another vehicle yet some form the conclusions are based solely on what the see.

Many are forming opinions, right or wrong based solely in UOA's posted. They have no idea of how the vehicle is used, what if any problems the vehicle haves and all the other variables to would contribute to the result. Some are changing brands every 3000 miles, looking at the UAO and coming to a conclusion. I think those who test oil would be very hesitant to come to conclusions that some here do, and the labs would see a lot more oil samples to compare.

Using 1, 2, 5 UAO's for the same brand is not conclusive data.

I will try to relate in the my work.
When we are determining position on the earth using GPS, we could just turn on our receivers (and many think its that easy) and would know within 20 minutes with relative accuracy where we are to 2-5cm. Yet we usually operate our GPS units (3 running at same time) for 5.5 hr continuously on 2 different days, and at different times to sample all the satellites. Our accuracy increases dramatical when we do this, we call it redundancy. Using the logic being used here by some, we would be happy with out 15 minute setup and hope all our future work and the highway plans and project are built and fit. If one of those extremely expensive bridge beams that are custom made are 5 mm short, someone it going to be in a jam.
I have worked on industrial trucks, big trucks tractors ,oil analysis is used to determine the condition of the oil and also if there are problems usually trending " many u.o.a.'s "is the best way to determine an onset of problems but not always, the best way to determine oil related problems would be to include a partical count as the usual analysis only measures less than 4 microns"I think" but if for example
Chevron Supreme shows excellent results in sound engines on many u.o.a"s,I would be inclined to say that Chevron Supreme works well. I think for us as consumers it is the only way to pick an oil because every oil company advertises their product as the best.

The three variables that determine UOA's are:

1) Severity of driving conditions - far and away the most critical parameter that affects the rate/type of oil degradation!
2) The mechanical condition of a particular engine - including any mods like aftermarket airfilters, performance chips, etc
3) Fuel quality and use of fuel additives - particularly for diesel engines.

You can make very general observations from the UOA's that are posted here. However, you really have to run an oil in the same engine, under the same conditions and using the same fuel to do a comparative analysis.

There is NO such thing as an "inconsistent" oil, but variations in the above factors can make the same oil look very good or very bad. I see very consistent results even with Redline, but the operating conditions and engine types vary widely ....


I am saying the UOA from one vehicle may not even be remotely pertinent to another vehicle yet some form the conclusions are based solely on what the see.

I agree with this. We might see a great UOA using Mobil 1 5w30 on a Honda Civic, but put that same oil in my LT1 engine and I bet it will show very high wear metals. Some engines just simply need thicker oils than others in order to show better results.

But like I said, using other people's UOAs as a general guide is still safe, just make sure to back it up with your very own UOA. Don't assume that because one guy went 10k on one particular oil, that you could do the same in your car.
I think many put to much reliability in these and there may no no trend there whatsoever. Its like saying I am not going to Disneyland anymore because it rained the last 2 times I was there.

Human nature, Mike. Confusing what one desires with what is. That's why science is so difficult for so many people--it requires detachment and discipline that is contrary to our basic tendencies.
Most people on here test pretty regularly. I think often we see at least two or three UOA for the same vechile in the same post. If it is not in the same post often their is a link. We also see alot of the same model of engine especialy if we are looking at a GM vechile. Models of machineery have similar wear patterns due to design, materials and manufactureing methods. If we know the engine model, time of year, oil used, driveing style, overall millage and UOA results it paints a very good picture. Is it crystal clear????? No! I can tell you this it sure beats takeing the Oil suppliers word that their product is best!!!

Lets say I line 6 guys up and shoot the first five in the head and kill them. Would it be silly for the sixth guy to make the decision that he too will die if I shoot him in the head? I doubt that the small sample size is going to matter much?

We natuarlay look for patterns in life to predict what is uncontrouble. It is good to learn from other peoples mistakes. Looking through the posts on a related topic can often identify trends. A good example is the elavated copper that most GM engines tend to have. The shearing and sludeing issues that some Toyotas have.

Until their is something better the current method seems to be produceing good results. I think alot people are useing this to help them pick an oil to try. I thin most still do an UOA once they have run it in their own vechile to determine if it is best for them!
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