Anthony:
If cars had "
oil flow gauges" as well as "
oil pressure gauges" a lot of people would change their minds about the viscosity of
oil they use.
QS, Shell, Castrol and the rest, get their base stock from all over the place. Don't think that QS comes from Pennsylvania, it probably doesn't. Many in the know feel that Pennsylvania base stock oils are actually better.
My newer Ford calls for 5W-20 oil. When I got a hold of Ford and asked them if I could use 0W-20 they said no, go figure.
Bob