GMC Repair: Alternator, serpentine belt, specialized tools

Question
1994 GMC 1/2 ton pickup 5.7l 4x4.  The alternator is making a whining sound that gets louder after a period of driving and increases in volume with engine speed.  I believe it is the bearings.  A new or rebuilt alternator is quite expensive and I am quite handy mechanically.  Is this a sign of the bearings going in the alternator and is there a kit to replace them and does it require any specialized tools?

Answer
Most likely a bearing, But very RARE. I don't think I have replaced more than a dozen in close to 25 years.

Make SURE it is the alternator and NOT another component and or the serpentine belt itself. These types of noises can be transmitted by the belt to other components making you think that the component is faulty.

Take the belt OFF, MAKE SURE that you make a DRAWING of the belt configuration BEFORE you remove it.

Once removed, hand spin the alternator and listen for any noises.

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