Why is 0w30 oil recommended for the N52B25?

As I said before it has nothing but 0w30 since new and every dealer and some independents I have ever visited will only use 0w30.



It's not like the dealer is the only one who sells LL04 spec oil. It can be brought elsewhere...



Wondering why they shook their head when I asked about 5w30.

Shell Lube Match recommends 5w30 or 5w40

Opie Oils and Castrol both recommend 0w30 or 5w30



What gives...