bearings usually growl. but if you let a unit bearing get real bad it can wipe out the brake as well. If you have never done this before, it will seem very difficult. you'll need some special sockets, an impact gun really helps to take off the 36mm nut since the torque is about 240lbs. and if the unit bearing is rusted in it can be challenging to remove it. but if you want to try I can give you a step by step on how to do it. easy way to tell if it's the bearing is to jack up tire, grab top and bottom of tire and pull/push if you feel movement it's the bearing.