Alternator Noise

[alvocado]

My alternator starting making noise this weekend and it sounds like bearing squeal. The truck is an '02 Yukon Denali, 6.0L with 144k miles and the original 130amp altnernator. I replaced both belts 3 mos. ago and I'm pretty sure the noise is not from the belts. I'm still showing normal charge. If this is a bearing in the altnernator, what is the likely part which is failing (pully bearing?) and can it be repaired vs. replacing the entire unit?

[05GMCZ71]

be absolutely sure it is the alternator and not the power steering pump or a pulley. I thought it was my alternator that was making the noise and so I replaced it. New one in, and the same noise was there. Wasted $200 because I did not diagnose it right. (The screwdriver to the ear thing does not work on things like this)

 

If it is the alternator, it is a piece of cake to replace!