1996 328i switched to synthetic oil - just read it can be bad for higher mileage cars

Hi,



I recently had an oil change done and switched to Castrol synthetic for BMW's (BMW LL-01) 5W40.

However, I just recently read that it's generally accepted that higher-mileage engines shouldn't switch to synthetic.



Is this true? If so, why? I thought synthetic was good for all BMW's, no matter the mileage. My car has about 165,000 KMs on it.



Thank-you.

1996 328i switched to synthetic oil - just read it can be bad for higher mileage cars