Most companies base their predictive maintenance programs on vibration analysis or interval timed, visual inspection. A more sensible approach to predictive maintenance is to monitor the equipment for changes that could be destructive in the future, but allow you to correct them before the destruction starts. I spent my formative years in nuclear power. If your blood pressure is too high you could get a stroke. A high fever indicates a need to get medical attention before destruction starts.
Some types of pains initiate an immediate operation.
You better check the fan belt and look for water leaks. Nothing is serious yet, but you should react to the warning signs. A loss of oil pressure means shut off the engine and react immediately. If it gets too hot you are going to have a problem. You had better correct the condition if you do not want to experience a premature seal failure.