As a lube engineer I look at several hundred oil analysis results a week. Generally I can spot a K&N or other aftermarket air filtered vehicle a mile away. 90% of the time the K&N's do a great job of keeping bricks and birds out but that is about all. And yet in about 10% of cases, the K&N works just fine, depending on one's environment, driving and particular vehicle. The K&N issue is just not black and white. From my perspective I advise anyone switching to a K&N to first run a stock air filter oil anlaysis baseline, then switch to the K&N/other aftermarket and check oil analysis again. If *all* parameters are in alignment, fine. However, we can't just look at dirt (silicon). Spectrographic oil analysis is limited to 5 micron maximum particle size. If one lives in an area where the predominant dirt particle size falls in the 5 to 10 micron size, we will not see it reflected as elevated dirt (silicon) in the oil analysis results and the stock oil filter will not be capturing it either. However, it will reveal itself in increased wear metals.
Ideally when doing an air cleaner check one should run both a spectro and particle count. This will reveal *exactly* what is going on in all contaminant particle size spectrums and allows one to know absolutely what is going on in the engine.
The Number One cause of shortened engine life is dirt ingestion. 80% of the alerts I see each week are from dirt contamination. This is why I am so adament for the necessity of checking with oil analysis not only for the K&N but stock installations also. Many of the trucks HAVE leaky induction systems right from the factory and the increased restriction of the paper element DOES create higher silicon levels due to unfiltered air getting into the engine. Switching to a K&N gives the false appearance that the K&N is filtering better than paper when it is only masking the induction leak.
George Morrison, STLE CLS
Ideally when doing an air cleaner check one should run both a spectro and particle count. This will reveal *exactly* what is going on in all contaminant particle size spectrums and allows one to know absolutely what is going on in the engine.
The Number One cause of shortened engine life is dirt ingestion. 80% of the alerts I see each week are from dirt contamination. This is why I am so adament for the necessity of checking with oil analysis not only for the K&N but stock installations also. Many of the trucks HAVE leaky induction systems right from the factory and the increased restriction of the paper element DOES create higher silicon levels due to unfiltered air getting into the engine. Switching to a K&N gives the false appearance that the K&N is filtering better than paper when it is only masking the induction leak.
George Morrison, STLE CLS