A method for determining a critical reduction in shaft speed in a work machine having at least one monitored shaft driven by a crankshaft of an engine includes determining an actual rotational speed of the crankshaft; determining an actual rotational speed of a first monitored shaft; determining a filtered rotational speed of the first monitored shaft based on an algorithm that utilizes the actual rotational speed of the first monitored shaft, the actual rotational speed of the crankshaft, and a reference rotational speed of the crankshaft; comparing the filtered rotational speed to the actual rotational speed of the first monitored shaft; determining whether the actual rotational speed of the first monitored shaft deviates from the filtered rotational speed by a predetermined amount; and activating an alarm if the actual rotational speed of the first monitored shaft deviates from the filtered rotational speed by the predetermined amount.