- Joined
- Sep 28, 2002
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The main reason for a used oil analysis ..as an integral tool for anyone ..industrial ..commercial ...whatever ...quote:
Further I might add, if used oil analysis have so many unidentifiable and thus uninterpretable variables, then there is no real basis at all by which to guage your engine's wear during extended drain. Yet Amsoil is the first to promote the accuracy of the used oil analysis in order to justify the extended drain interval. You can'y have it both ways.
IS NOT FOR WEAR. It is for "suitablility for continued use" (visc, tbn, insolubles, oxidation, nitration, TAN, etc.) and to point to potential pending issues (coolant, etc.)
That doesn't mean that you won't attempt to minimise wear metal indicators based on the inferential data.
used oil analysis is a tough deal for most of us. It is far easier for the commercial/industrial user who has ONE spec'd oil and one assumed service duty. They don't have any control over wear ...so the only thing that used oil analysis tells them is how the oil did. They don't have 72 different choices for their engines (Mack/Volvo spec xxxyyyzzzJB2, Ingersol spec 302-AB23 spec ..etc.)
That being said ....surely if you see 24 ppm with one oil over 12 ppm with another in like service ..you're going to go with the one that shows the lower number(s). It can be anything from a change in viscosity ..or a change in viscosity within a given viscosity range ..or "it's a "thicker" 30 weight" (visions of Hudson as he responded to Hicks in Aliens when Hicks said "Man, it's hot a h-ll in here!" ...."Yeah man, but it's a dry heat!" as they entered the steamy reactor building) ..or merely a change from one additive pack over another. We have no way of determining where in the engine the higher metals are coming from ..or why. We don't know whether it is, in the case of bearings, one bearing ..all bearings ..or half the bearings
We've had debate after debate over used oil analysis with the fundamental question being "doe it measure wear?" We can't say that it measures it ..but it surely has some relationship to it ..and we tend to react to it in the belief that less is better.