Depletion over time

[mjoekingz28]

Hate to double post, but what happens at it sits?

Does the oil just lose it qualities?

Or is the oil actually etching the metals in the crankcase/engine as it just sits there?

Or what?


Thanks for delving into this!

 

[Pontual]

Absorbs moisture and when run, that modifies some characteristics of base and add pack, specially raising the acid number, leading to oxidation and corrosion, since acids make way to water get in direct touch with the metal parts, that was once protected by the oil.