Water Pump Prob Update

[97tahoe]

I posted a short time ago about a winding sound coming from my '97 Tahoe. I thought it might be the water pump because the alternator checked out as "good" when I had it tested at the local Auto Zone. After placing a long screwdriver on various engine parts I found the winding to be coming from the alternator.

My question is does this mean the alternator is definitely bad, do I have time to replace it, or should I replace it asap before I am 100 miles away from nowhere and end up stranded?

I know the Auto Zone test doesn't always mean much but it's giving me a false sense of security to let the repair wait. Also, my battery gauge hasn't started dropping at all and in fact is at times slightly higher than normal so being a novice at most repairs I need your opinions/advice on what to do.
Thanks!!!!

 

[mygreen98]

the noise is one of the shaft bearings in the alternator, not he alternator itself. its ability to continue to charge the system will not be compromised until the bearing completely lets go. at that time it will seize up and yes you will be stuck. with the truck not running spray a little lubricant(wd40) on inside of the center shaft, then start the truck. if noise goes away aliitle or changes , suspect bad front shaft bearing, if not its the rear one. either way, plan on changing alt soon. good luck