You can always pull it out and look at it. If the tip has any wear then the sensor wheel is making contact with the sensor and the hub needs replaced. I always just replace the hub. I would hate to spend $75 on the sensor, then in a few months I have to spend $200 to replace the hub because the sensor went bad again. Some info for you the resistance of the sensor should be between 855 and 1230 ohms. I don't know if that will help you with your decision, but it gives you more to test. If the resistance comes back ok then I would assume that the sensor wheel is rubbing the sensor.