Apart from the ingress of debris, the greatest danger to any design of a pump is cavitation. The phenomenon can be found in centrifugal (i.e. impeller) or positive displacement (i.e. gear, gerotor or vane) pumps, in both oil and coolant applications. Excessive cavitation can lead to erosion damage. It is important to understand how cavitation occurs as there are some misconceptions and confusion on this topic.