> > >>> You could buy three identical cars, keep changing the oil on all of them
> >>> with a different kind of oil in each, and try and rotate your commute
> >>> around all three of them so you put about the same mileage on them. Then
> >>> you could do long-term oil analysis on each and five or six years later
> >>> probably get a good idea of how each of the oils is doing. I could see
> >>> someone doing that.
> >> Such tests have been done, and no advantage was shown for synthetic oil.
> >> However they did not do extended change intervals. It could be that if
> >> they had gone 7500 or 10,000 miles between changes that they would have
> >> found an advantage to synthetic.
>
> > If possibly you are saying synthetic has ho benefit put some regular
> > oil and syn in the deep freeze and see which one pours at -15f better,
> > it also doesnt burn up in high heat like regular oil. Cold startup can
> > really starve a motor of oil.
>
> Yes, in extremely cold climates, and in very high performance engines
> that run very hot, there's an advantage to synthetic. The issue is that
> so many people use synthetic in mild climates and in normal engines, and
> also don't extend the oil change interval. They're throwing money away
> because all the tests show no benefit.- Hide quoted text -
>
> - Show quoted text -
Not extreme cold is needed to benefit, even at 20-30f oils dont flow as well as they do when warm, also there is a group of earlier toyotas known to sludge and ruin motors from the motors higher operating temp, synthetic would have been a big benefit to them. I use it, I notice a diference, oil is cheap compared to a new motor.