[jmillet]

Originally Posted by toattett

I just picked up the car from the dealership after a "Low Mileage Oil Service" @ 8000 miles on the clock because my last "Break-in" Service @ 1200 miles was over a year ago.
However, in the service invoice, it says they have used 8 QTY of 07-51-0-017-866 5w-30 Synthetic oil in the car and it's covered under warranty. As I remember, M engines are suppose to take Castrol 10w-60 (part no. 07-51-0-009-420). I looked up my 1200 miles service invoice from a year ago at a different dealership, and they did use the 10w-60 oil.
Am I missing something here, or is my concern valid?
Thanks!

You're dealing with an incompetent dealer. BMW NA emphatically recommends Castrol TWS 10W-60 oil for the S54 engine; read the label on the radiator cover.
You might also want to check the oil level to see if they over-filled the crankcase. The S54 engine takes 5.5 liters; no more, no less. Again read the radiator cover label for oil level instructions.
No immediate harm done, but I'd climb the dealer's tree over this faux pax. I'd insist on an immediate oil and filter change as well as annotating the records that the wrong oil was installed in the event of any future engine lubrication related warranty claims.
I'd also find another dealer to do my maintenance and warranty work. Or better yet do it yourself.