* Here's a timeline for motor oil classifications for all classifications.
* The age of your 'worn out' car reflects on the types of motor oils available over it's service life.
* 'New' motor oil parameters are restricted to 'new' oil. What it is, and how it's treated, bear upon what happens inside an engine, between oil & filter changes.
* Your owner's manual will provide you with the appropriate types/grades of motor oil for your car, as specified by the manufacturer when the car was new.
* What was actually used will impact what actually happened to the engine.
----------------------------------------------------------------------------------------
This is where I'll start the 'Boron' conversation. All related discussions will be handled under dedicated headers.
https://www.api.org/products-and-ser...s#tab-gasoline