Usually the word “myth” or “mythologies” refers to beliefs that seem to be perfectly true or immutable. Although machinery vibration understanding is not a religion, it certainly has its beliefs that are usually true, but also beliefs that the writer has found to be “not true.” Those that are strongly held and not too often questioned, are by the writer called “mythologies” – vibration related. This presentation is not based on a play with words. Instead, the myths to be questioned were chosen, based on the harm it creates for those trying to either solve