Hi,
I have a 2003 maxima i just replaced my alternator a day ago an its making a whistling noise an i noticed it got a lil louder when i turned my lights or heat/AC on, is this normal?will it be fine?would like to figure this immediately.Thanks

 

Perhaps your belt is loose and slipping, or the alternator has a bad bearing. Your need to figure this out - I would start by tightening (or loosening) the belt a little bit, and observing how/whether the noise changes.

 

I just went to my mechanic, he figured out it is the alternator, he checked the charge on the battery an its fine, then he told me since the alternator is new it could be that it hasnt broken in yet an noise could go away after its broken in, is this true? Or if the bearing is bad what would i need to do? Trying to figure this out asap please let me know.Thanks

 

^This.

And alternator's don't need to be "broken in." They should be whisper quiet right out-the-box. If adjusting the belt doesn't help, you likely got a junk unit.

 

I got a junk unit then, i just dont want it to give out on me, i dont mind the noise i just dont want it to give out,im also thinking about selling it an buying a 1997 honda accord that was my first car an i barely had problems with it only problem i had with that car was the starter which was a cheap fix..do you think the alternator will give out on me since its making that noise?

 

Some alternators will whine/whistle when under a light load and get louder under a heavier load. The alternator isn't necessarily bad but it is annoying. If it is not that loud, you can choose to ignore it. Or you can choose to change the alternator. Your choice.

 

Thanks man that made me feel s bit better about the situation i don't mind the noise i just dont want to break down you know