My two cents will be determined by the current mileage of your ride.
I have a E71 X6M. I'm nearing 60k miles and just did an oil change. The dealer recommend and changed my oil to 0w-30 from 5w-30.
My first assumption
:will be to prolong engine life being that your mechanical parts are aging and it will put less effort to churn thicker oil and helps make the engine run more efficiently.
My SA said it's time to change, not gonna argue that, cause if anything the "potato" is in there hand.
It's more pros to lighter oil anyway. Plus you get about 2-5% better fuel efficiency. Pending how heavy you are with your foot.
CHEERS Bro
