Interesting article. I do my vehicles once a year since they don't accumulate many kms (the cars about 3000 each as one is for winter, the other for summer) and the truck is lucky to see 1000km a year.

MC wrote:

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 until you put it in an engine and add all of those combustion by-products to it, heat and cool it, add condensation, etc.

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 Yes, supposedly those conditions put a lot of acid into the oil and if you let it just sit without any circulation or oil changes the acid corrodes bearings. 

The maintenance schedule for my VW Golf recommends changing the oil every 15,000 kms. To me that is far too long, but I do notice that my oil does not drop or get discoloured. Tight tolerances, low-tension rings, precise fuel metering (so no fuel wash) all add up to cleaner oil for longer.

Now as for older carburated vehicles, especially the older 261 sixes without an oil filter, oil changes need to be more frequent. The best way to determine oil 'soundness' is to draw a sample and send it in for oil analysis. That will reveal whether your oil change schedule is good or not.