How efficient is synthetic motor oil to make.

[jimbo64]

if the oil is clean but the additives are depleted wonder why someone hasn't marketed an additives package to just add to rejuvenate it to get longer life. this sounds like a no brainer-

 

[sw03]

if the oil is clean but the additives are depleted wonder why someone hasn't marketed an additives package to just add to rejuvenate it to get longer life. this sounds like a no brainer-

Umm, this is the bases for Amsoil and some others (ie, bypass change).Problem is cost will become an issue.