My brother informs me that when he was driving on the highway yesterday in his BMW 530xi he heard tap (tappet) noise. He put in a can of oil. Noise lowered. But 100 miles after the engine flashed signs that engine is shutting down. He pulled to side and the car computers shut down. There was some oil on the ground. But the engine oil level is not dangerously low. He does not think its transmission fluid but engine oil that has leaked. He was towed to a nearest hotel. He is waiting to take his car to the BMW garage this morning.
What do you all think is the issue? (By the way he had a recent oil change done).