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Old 08-26-2018, 07:23 PM
alacey alacey is offline
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Location: SATX
Join Date: Mar 2018
Posts: 256
Mein Auto: 2014 328D
Originally Posted by Nadir Point View Post
I don't think you understood my post you quoted at all. Unless you are measuring air filter restriction with a vacuum gauge or FillterMinder and tracking your change intervals you will never notice any difference except how long it lasts before you need to change it. The only time you could possibly EVER see a UOA effect from an OEM or OEM-equivalent air filter is if it is physically damaged or defective and/or improperly installed.
Higher silicon levels in a UOA would tell you that more dirt is getting through the air filter and into the oil. If silicon levels increase with all other variables staying the same, then that is a sign that dirt is getting into the engine. If I test my oil with the current pre filter and then test afterwards without the prefilter and my silicon levels increase, then that is a clear sign that more dirt is getting through the air filter in the time I have it in. I don't care about it lasting longer than my yearly change interval as I stated. If the silicon readings are no different between the two within that time period, then I will go with the one that is either cheaper or provides better efficiency to the point that it pays for itself it is a higher cost.

"Used oil analysis, Cummins notes, can monitor engine oil contaminant levels and provide evidence of dirt ingress, excessive fuel contamination (dilution), coolant leaks, excessive soot accumulation and abnormal wear. For example, elevated levels of silicon in the used oil indicate dirt contamination usually caused by faulty intake filtration. The used oil can also contain abnormal levels of copper and lead from bearing material wear, even without extremely elevated levels of chromium and iron being present."

Interpreting used oil analysis

"Silicon Dioxide (sand & dirt) is a common
contaminant may indicate a faulty air filter or
seal. May have also entered when top-filling."

The Oil Analysis Handbook

Last edited by alacey; 08-28-2018 at 02:23 PM.
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