I could not find any 4 stroke mineral oil from Seadoo. The dealers told me that Seadoo no longer make it, and recommended semy synthetic oil. I know that on SC Seadoo's can't use synthetic oil because wil damage the SC. I replaced my oil pump and I tried Castrol 10W40 with the same specs as Seadoo oil and it's not good (doesn't burn it, but makes foam -as the machanic told me it will happend if the oil it's inferior to Seadoo specs). Oil brakes on high RPM's. Today I changed oil and filter using Exxon (all spec: SM, SJ,SH,SG,SL). I hope it will work. It's any other oil which can work with RXP supercharged engines?