G20 Belts Squealing!!!

[BTLines]

I have a '95 G20 and this is my second go-round with an alternator/AC belt that squeals incessantly! This time it began as soon as the heavy rains started, but it does it any time it's cold outside, wet or dry. I replaced both the alternator and power steering belts this weekend and now the squealing is WORSE! Spraying belt dressing on the belts helps for about 5 minutes, that's all.

I know the obvious answer is that the belt is not tight enough. But last time I did this I tightened the belt until the squealing stopped, and the ($297!!!) alternator failed 3 days later. I assume that over-tightening the belt caused the bearings inside the alternator to overheat. I don't want to make the same expensive mistake twice!

Anybody got any ideas or had a similar experience?

[driverdriver]

This is a guess, but I had this problem on an old domestic. It was eventually attributed to humidy and than engine bay heat causing the alternator belt to slacken a bit causing squealing. Installing a brand new belt from another manifacturer solved the problem.