Hi

engine related but not subaru engines, yamaha waverunner engines actually. My 4 stroke jet ski is low on oil for some reason (thats another story) and i have found out it requires 10W-40 oil. Would there be a difference with valvoline 10W-40 and castrol magnatec 10W-40? Is magnatec going to make a huge difference or not, the valvoline is recommended by the manufacturer apparently, but wondering if the castrol will hurt it at all?

Any help appreciated.

Marty