1998 Cadillac STS

Electrical problem
1998 Cadillac STS V8 Front Wheel Drive Automatic 129000 miles

I have never had alternator problems, the car is 10 years old.
I heard a very loud noise when I turned the engine to start.
When told this the mechanic immediately said I need an $700 alternator, plus he said the voltage was at 11.

Now is it possible I need bearings because they are bad in the alternator instead of buying a brand new alternator.
Would it be cheaper to just replace the bearings in a car like this?

Thank you
February 15, 2010.

I don't know if you can even get parts to service the alternator. This noise, was it just brief, or does it continue when the engine is running? If you have issues with low charge output, it would be more than bearings.

Feb 15, 2010.