Oil Change Surprise

I normally do my own oil changes for my 2011 328i (Castrol 5w30), but I’m in between moves and didn’t have my equipment so went to a local mechanic who specializes in BMW/Mini. To my surprise, they put in 5w40 instead of 30 stating it was “better in their experience.”

Should I change it back to 5w30 ASAP or just let it run thicker oil for a few thousand miles?