API SN increase milleage?

[Sylvert]

I noticed that pennzoil platinum is API SN, compared to other that are SM, apparently SN get better milleage and better high heat protection. Is this true?

 

[Rand]

Theoretically they raised the bar a little from SM

but most syn oils already annihilated the api SM limits

and most were barely reformulated for api-SN (or not at all)

 

[skellyman]

The more important thing is the choice of weight, a 5w20 will get better mileage vs a 15w50 or a 20w50.
Just a thought.