</font><font color="blue" class="small">( Wishful thinking.... /forums/images/graemlins/wink.gif
Hydrodynamic oil boudaries are 1-2 microns, NOT thousands of an inch.....
FYI, in a diesel engine, the soot particles are 1-5um and they act like sandpaper.
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Well, maybe, but how much REAL WORLD damage does this cause? Over the road Diesel trucks run 750,000+ miles between overhauls with sooty, black crankcase oil.
As I said, my old Toyota Tercel ran 320,000+ miles with ~5k
oil changes of crappy old "SF" oil; whatever brand was on sale with house brand oil filters. The oil was always dark brown to black by the time I changed it. The engine never had any internal problems. It had good compression. No major leaks, only seepage. The car's body had cancer, The seats were shot. Bottom line, the rest of the car wore out before the engine. I could have fixed it, but I was simply tired of the car after awhile.
I don't want to get into an import vs. domestic discussion here, but some engines are better engineered than others.
Some engines are engineered so well that extra virgin olive oil could be used in the crankcase (I'm joking).
Testing labs have people scared into thinking that a TBN that's off by a few numbers or a few PPM of wear metals means that a person's engine will self-destruct at any instant.
No wonder they call it oil ANALysis. /forums/images/graemlins/grin.gif