Got a 03 I35 and the alternator has been making this whine sound for a few months, im assuming the bearing have gone bad on the pulley possibly? I wanted to know if the alternator pulley can be removed from the alternator while its still on the car? Has anyone done this before. Ive already replaced the idle pulley to rule that out as well as the belt. The noise is anytime the car is running, seems to be getting louder now.

 

last time I heard an alternator making a whining sound was on a friends car and it died shortly after.

 

Mine did the same thing, started with the metallic whine (almost sounded like a SC) and then it wasn't making enough voltage to support the additional electrical load. (AC, headlights, etc)
Had it tested at Autozone and it failed the diode test. Voltage across battery was under 12V with engine running at 2K RPM. It might be time to replace the alternator before it kills the battery and leaves you stranded.

 

Alternator is likely on its way out, not even worth messing around removing the pulley with it in the car still etc just replace it

 

There is no bearing on or in the pulley. Any bearing replacement will require removal and disassembly of the alternator.

 

just go on Rockauto and get a 125 amp 4th gen alternator.

 

Thanks for the replies guys, I may just go and replace it although its a pain to do so. But I def dont want to be stranded anywhere.

 

it's not a hard alternator to change out. just be careful unplugging the connector. you might want to actually order a new sub harness for the alternator, I'm on my 3rd..

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