reccomended maintence schedule

wrote in

Not mine. I just happen to own a Honda. And I happen to trust Honda's
judgement better than my own, for the most part.

High-end cars like Mercedes actually do now have sensors that sample oil
quality and recommend replacement based on an actual analysis.

Honda and most other makers do it by calculation. The calculations are
arrived at by considering driving habits and ambient temperatures. The
algorithms used are fairly sophisticated.

Your objection sounds like the ones expressed by steel-furnace men a
hundred years ago, when pyrometers were being introduced to help better
control furnace temperatures. The furnace men were insulted, figuring
they were being told they didn't know what they were doing. Of course,
it turned out the pyrometers were far more accurate than human eyes,
which is why all furnaces mow have pyrometers.

None at all. Honda assumes the dealers are following factory procedure,
which may or may not actually be the case. Honda and its dealers have a
love-hate relationship.

Mercedes got into trouble a few years ago for just this. The oil
monitoring system of the time was expecting factory-specific synthetic
oil, but the dealers were installing regular oil. The result was heavy
sludging and a class-action lawsuit.

Honda dealers are independent companies that have purchased a Honda
franchise from Honda. They are under no obligation to use Honda repair
parts, use Honda tools or follow Honda procedures. This is one reason
you'll find wide variance in dealer quality.