I have searched for this, but I didn't find anything on it.
Can anything adverse happen if I started running synthetic on an engine that has 250K kilometers on it already?
I'm not sure what the car has been running previously, I'm assuming regular dino 5W30.
And if there's no bad effects, what would be the right one to run, 5W30 or should I go 0W40 ( keep in mind I'm in up north )?
Thanks in advance!
