Depends what you mean by "damaged". Repeat bearing failure is caused by pressing on the center portion instead of the outer ring, or by placing the vehicle's weight on it before the axle nut is torqued to specs. Pressing on the center of the bearing forces the marbles into the race which makes many little dents that cause a humming sound. A similar thing happens when the bearing has to support weight before it is held together by the axle nut. Often people set the vehicle on the ground to hold the axle from turning while they tighten that nut, but that's too late. It's far easier to stick a punch in the cooling fins of the brake rotor to hold the axle while the nut is tightened.
That torque value is critical too. You must tighten the nut with a click-type torque wrench. Most bearings call for around 180 foot pounds, but some go as high as 240 foot pounds.
It also is impossible to remove pressed-in bearings, then reuse them. They must be damaged to be removed, but there is no reason to remove them except to replace them.
Wednesday, March 20th, 2013 AT 12:15 AM