What are the consequences for the owner of a car from which a wheel fell off, causing a man's death?

No one may be held responsible for a car accident if it occurred naturally without negligence, but the driver may be held responsible if the accident resulted from his negligence in driving or preparations. If the driver took all safety precautions and there was no negligence on his part, then he is not held accountable for what happened that he could not avoid. The Sharia court is the one that determines responsibility in such cases if the driver does not admit his negligence.