If you go to ExxonMobil in NZ or AU, basically you can run any viscosity in any engine. For instance, for most Honda's, you could run a 5w30, 5w-50, 10w30 or 10w-40 and even a 20w-50. These were recommendations from the ExxonMobil Lube finder. So I guess what I'm saying is, other then NA, run what ever you want because they obviously do in other parts of the world. These Honda engines BTW, were as small as 1.8 and 2.0L.
*Could their be a difference in the type of oil pumps being used on our cars vs others?
*Could their be a difference in the type of oil pumps being used on our cars vs others?