I have 3 cases (18qts) of Pennzoil Performax
5w30 full synthetic that is rated for SH service. Since this is a PAO (I believe) would it be OK to use in my current car which calls for SJ oil. What are the negatives of using it?
The additive package would be stronger for SH oils. So if your vehicle has a CAT installed, it would poison it quicker than if you were using a SJ or SL oil.
Johnny , Thanks for verifying that Performax is a PAO. How does it compare with Mobil 1 ? Also do you know anything about Slick 50 synthetic (also SH rated) I have a few quarts of it also.
Regarding the cat converter fouling sooner with
SH oil what mileage are we talking about? Am I to believe that SH oil is as good as SJ (maybe better) and that the only issue is cat fouling due to greater amounts of phosphorous in SH oils?