Getting the most out of your UOA

[Solarent]

Part one: Introduction

Since many of us are regularly having UOA done on our vehicles, and have seen often good results from using high quality oils, good filtration and the like; I thought it would be good to post some information that would be helpful for the new members or for members who are thinking about UOA for the first time.

If you haven't read this already I strongly encourage you to do so:

http://www.bobistheoilguy.com/engine-oil-analysis/


There are many reasons why you might want to get a UOA done. Here are a couple of the main ones-

-You would like to start moving to an extended oil change interval.
-You are looking to catch engine maintenance issues.
-You are concerned about an engine issue and are trying to find the source of the problem.

One of the most important principles (and often overlooked by beginners) behind doing UOA is that it is a statistical analysis based on a trend. So what that means is you can't look at your first analysis and think you know everything about your engine and oil. You need to first establish a trend over multiple UOA and see what is happening and considered "normal wear" for your engine and your driving habits.

While looking at other people's analysis can be helpful - especially if they have the same engine and use the same oil; it will not likely give you any sense of baseline or trend averages that are applicable specifically to you. The same can be said about the "averages" that you get back from the lab. The best thing you can do us establish your own trend and determine the "normal" values for your engine and driving habits. Typically I recommend having at least 3 baseline points on your UOA to establish your trend before making any serious changes to your maintenance program.

 

[Solarent]

Part 2: using UOA to extend your OCI

After you know what is considered normal for your engine on the oils you are currently using (for example using a Gr-II with a 3000 mile OCI) you can then consider extending your OCI:

If your UOA shows little to no wear, good tbn/tan, little change in viscosity, and good retention of additives than the oil you are using is likely a good candidate for extending your OCI. All of these factors are very important as they each tell their own story about what is going on in the oil. Many individuals will put higher value on specific aspects of your UOA but in reality each section is about equal in helping you to understand and address engine oil issues.

If your results are mediocre or worse than you should select a new oil (perhaps in our example change to a Gr-III OR Gr-IV synthetic oil). When selecting a good oil, refer to the product data sheet info, a virgin oil analysis (VOA - which is typically the same oil analysis done on for a UOA except on new oil) or research what others have done using the boards at BITOG.

 

[Solarent]

Part 2 cont'd - using UOA to extend your OCI

The next part is often missed by many oil users. Run your new oil for the same length as your existing oil. This may seem like a waste of money - using a synthetic for a relatively short (3000mile) OCI, but it can be the only way to ensure you can compare how the new oil performs under the conditions in your engine. Because your baseline is set using oil A at 3000 then the comparison NEEDS to be using oil B at 3000. If you increase your OCI right away then you will get mixed results and it will be harder to evaluate your new oil's performance under your engine conditions. Now many users will say that you can switch to brand x and immediately increase you interval to 10k miles or more because it worked for them. And if you want to take their word for it by all means it is up to you. BUT, that approach negates the primary purpose of UOA which is using the comparison and trends to evaluate your engine.

So now you have selected a quality oil and compared it to your previous results you can begin to extend your OCI. Typically I recommend that you do this in stages up to your desired maximum. (so if you are looking for a 10k OCI then start with an increase to 5k, then 7500, then 10k).

I realize this may take up to 3 years to complete this process, but to be prudent and ensure that your driving conditions and engine and oil choice combination are reach their maximum potential OCI. At each interval you should be reviewing your analysis and watch for spikes in your trend. Usually when using a quality oil then you will see small changes in your parameters indicating that the oil is being used. This is manifest in elevated wear metals, changes in viscosity, TBN or TAN, or a decrease in additives.
The only way to read an analysis correctly is to recognize if the results make sense based on your trend. So a the changes in your result vs the shorter OCI should make sense in that it should be a balanced shift in values or be easily explained by understanding the relationship between each of the parameters.

 

[Solarent]

Part III - Using UOA to troubleshoot or watch for potential issues.

Once you have reached your maximum OCI and are happy with it then you have the opportunity to use the trends you have established to watch for abnormalities in your trend.

It is quite common for people to make a change in their oil or OCI and see a large shift in wear metals or other indicators of engine issues. However this is only valid if it can be confirmed with a second sample. For Example once I pulled a sample and the container I put it in had recently been rinsed with water and allowed to dry. This gave a positive result for water and caused some initial concern. However taking a second sample verified that it was contaminated by the container and not in the crankcase.

Proper monitoring using UOA depends on following the trends and identifying abnormalities in the history. By doing this process you can become well acquainted with your engine and the process of UOA. If you've done this and get stuck then come online, post your analysis and trend info and then ask for a hand . The great thing about BITOG is that there are always some individuals who are willing to give their two cents to perfect strangers.

Many times costly repairs can be avoided by properly evaluating shifts in your UOA parameters. Bearing failure, component fatigue and other engine issues are often manifest in the UOA results if you know what you are looking for.

Often the lab you use will make recommendations or comments on your analysis. These results are always more accurate if the lab you use keeps your history and trend information on file.

 

[Solarent]

Part IV conclusion

By providing this basic information and by reading the other resources referenced in Part I we hope that you will find more value in your UOA. Maintaining your engine in an attempt to maximize the performance and protection takes time and effort and can be confusing for those who are first starting out. Even the brightest and most knowledgable members had to start somewhere.

There are many resources available online to help you learn and understand what is happening inside your vehicle or equipment. That is one of the primary purposes of BITOG; to share knowledge and experience. And to get into the occasional disagreement over whether PU is better than RL, RP, M1, AmsOIL etc etc etc.

Happy analyzing!

 

[Quattro Pete]

Originally Posted By: Solarent
If your UOA shows little to no wear, good tbn/tan, little change in viscosity, and good retention of additives than the oil you are using is likely a good candidate for extending your OCI.

[...]

If your results are mediocre or worse than you should select a new oil

I understand the point of your post was to provide some simple to digest info for those new to UOA, and this required you to make some generalizations. However, the particular statements I quoted above are questionable at best, IMO. Many of us will argue that a typical $20 UOA cannot be used to compare oils against each other, despite many BITOGers attempting to do so.

Just because a UOA shows low metals and good additive retention does not necessarily mean it's the particular oil's credit. It may just be a well designed healthy engine and you might possibly get the same low metals regardless of what oil you put in there. And by the same token, if your results are "mediocre o worse" (what does that mean exactly?), it's not necessarily the particular oil's fault. You may have some other issue that is causing it.

Again, I commend you for your effort. I would just caution people to be careful about drawing conclusions from inconclusive data. I've been guilty of it in the past as well.

Originally Posted By: Doug Hillary

Firstly, it is important to realize that you get what you pay for. The most common forms of UOA are limited in their scope. It is a case of if you pay more you get more. So my comments here relate primarily to the “simple” UOAs – the cornerstone of those appearing on BITOG

Secondly, it is easy to assume that by carrying out a UOA you will be able to determine how quickly the engine is wearing out. As well, if you change lubricant Brands you will be able to compare the wear metal uptake results and then make a balanced best lubricant choice to make your engine last longer.

Sadly that logic is seriously flawed.

http://www.bobistheoilguy.com/used-oil-analysis/

 

[Solarent]

To QP. Thank you for your input. I have come to respect your opinion very much and agree whole heartedly that the oil may not be the only reason an analysis comes back with favorable results or poor results for that matter. And all newbies to a UOA program should be aware of that. By "mediocre or worse" I was referring the results as compared to the trend you have established. Like you point out poor results doesn't necessarily mean bad oil. What we are attempting is to finding an oil + OCI combination that maximizes the drain potential for your specific engine.

I appreciate the link you posted I meant to put that in as well. I do however think a 20$ analysis with a statistical trend will allow users to at least get an idea of what is going on although more extensive UOA can help troubleshoot more specific problems. That said just because one person gets good/poor results in their engine with one type of oil does not mean we can conclude that an oil is good or bad. This is why it is important to establish your own baseline based on your oil / engine combination.

To everyone else: as stated above it is the trend in your engine that is the most important and not all oils are compatible for long drains on all engines. The key is finding the oil that gives you the best results based on what your baseline indicates and slowly working to increase your OCI from there. If for example you switch to a synthetic and get good results a 3000 and a spike happens at 5000 or 7500 then you have to factor that in to your plans to extend and that could be an indication that your engine may not be suitable for longer drains on that specific oil it could also indicate that something may be happening inside your engine and should be investigated before extendin your drain even further.

 

[Jim Allen]

Solarent- Good summation and potentially worthy of being a sticky.

In a similar vein as Quattro, the part missing in your treatise is further explanation on the importance of the operating conditions and how they will effect the OCI. Also, I agree with Quattro and Doug, more emphasis on the fallibility of using small changes in elemental results as a major indicator of engine wear... "OMG... my iron is up 20 ppm!" Using TBN, TAN Oxidation and Nitration as OCI indicators is a more fruitful endeavor.

I think you know these things but newcomers may not, so it's all worth mentioning.

 

[Solarent]

Agreed... Wayne has actually asked that I make some revisions as they would like to add it to our UOA library on the main page. I will make some adjustments using yours and QP's suggestions.

If anybody has any other thoughts that should be included I am game to hear them. I will put in my changes sometime before the end of this week.