Originally Posted by Talent_Keyhole
Originally Posted by CourierDriver
I know oil analysis is a big deal, but I have never lost an engine do to oil ....
Catastrophic, sudden, mechanic engine failures are rarely identified beforehand by oil analysis and normally not caused by oil. In that sense I agree. Have engines experienced shortened life span, severe wear from wrong viscosity, over-filling, poor quality oil, severe contamination, sure. Most people do not keep their vehicles long enough for an engine failure or be able to ascertain a shortened life span. There have been a few cases where junk oil (API SA) and even used oil has been re-bottled and sold on the market. In those cases damage was caused by the oil alone.
I, too, have never lost an engine due to oil failure, or a filter failure for that matter.
But that does not stop me from doing used oil analysis. Because used oil analysis have more than one purpose.
used oil analysis can, but will not always, predict a component failure. There a lot of "what if ..." scenarios here; too many to make a blanket statement other than to say used oil analysis can see some instances of imminent failure, but not all.
used oil analysis are first and foremost a fiscal savings too, although you'd not really know it given how BITOGer use them as toys. used oil analysis are most effective at deciphering wear trends, and then using that knowledge to set reasonable OCI cycles. If the used oil analysis shows good wear, low contamination and decent physical properties, then you should extend the OCIs out. You do that in a continued fashion until you reach some condemnation point. Why do an OCI at 5k miles if all is good at 10k miles? Why OCI at 10k miles if all is good at 15k miles? In large sump systems, you can often see OCIs go 30k to 100k miles (typically in OTR trucks).
There is a caveat; used oil analysis can cost as much or more than an OFCI at times, so the ROI really isn't great, especially on small sump systems. Why pay $32 for a used oil analysis for you 2-qrt riding mower? Why pay $28 for a used oil analysis when $25 will fill your sump? In these circumstances, I advocate for used oil analysis to establish a mantra, then cease the used oil analysis until an issue is suspected. For example, I used used oil analysis data to prove that 10k mile OFCIs are safe for our 4.6L Ford engines; the data repeatedly shows no ill effects. After establishing the safe trend, I then stopped the used oil analysis. I will only get another used oil analysis if I see something go awry; smell of fuel in the oil, appearance of coolant in the oil, audible noises that would indicate mechanical issues, etc.
PCs are also a tool. They have benefits, but also limitations. They help you understand particulate loading, but they don't speak a word to the substances found. PCs tell you about loading, but used oil analysis tell you about elements. PCs will tell you how large something is, in a delineated scale of concentration. used oil analysis will tell you the composition of the element, but not size.
The better way to manage a maintenance program is to use the tools (PCs, used oil analysis, physical observations) together, and understand the pros/cons of each tool used in concert with each other.
