Thinking about an actual oil sensor(s) to determine when oil needs changed is interesting. I could easily see a sensor that would read the oil amount and the possible resistance reading across the oil with microscopic metal particles suspended in it.
The oil "sensor" everyone is talking about is not a "sensor" at all. It's really an oil life Calculator. The industry has developed them over several years of testing. They ARE for the most part fairly accurate.
Consumer Reports did a taxicab "test" many years ago (1996) running HUNDREDS of thousands of miles, with engine teardowns and oil analysis and they found that 6000 miles is still VERY conservative for the average car.
Here's the article
The sensor you mention doesn't exist (by itself) ........ Just take a look at a Blackstone Labs oil analysis. They test for a great many different components in the oil (including stay-in-grade) to generate a report. Their test equipment costs hundreds of thousands of dollars. You're not going to get a valid test of used motor oil just looking for microscopic metal particles. Besides, if the microscopic oil particles are so microscopic that they don't get "stopped" by the filter, they likely don't hurt anything at all.
They DO tell you that something is going on that possibly should be addressed. But if a sensor only told you to change the oil based on that, it wouldn't really be telling you what you REALLY need to know.
Back to the OP's question.
Are the "Sensors" accurate? Sure. The manufacturers put a LOT of research and development and have have staked their warranties on them. Cars nowadays easily go 200,000 miles and more (
following the manufacturers OCI advice of course) with little or no significant engine problems (and those "problems" are usually NOT oil related).
So I would suggest that in anycase, when following the manufacturers advice on oil changes (Boat, Car or Truck) even if there's a computer telling you when to change the oil, You STILL won't go wrong.
:deadhorse:

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