I had my 328i engine oil replaced at BMW dealer with odometer reading of 7800 miles. They used Castrol 5w40
on it, and they put a sticker for the next replacement of 11800 mile. Any opinion if there're better engine oil than Castrol like Mobile? Also, I don't understand why dealer marked 11800 mile for the next oil change while official BMW recommend the first oil change at ~15K miles.