Replace the belt.
Usually a squealing sound upon acceleration , or even just revving the engine in neutral , indicates a worn or loose fan belt .
Check all belt driven accessories to see if one has a bad bearing or is binding
Could be a loose or worn belt, or an accessory (water pump, alternator, etc.) bearing going out. Could even be a wheel bearing going out. Start by checking the condition/tension of the drive belt(s),
I replaced an alternator on a 2002 Nissan Altima but the drive belt is now too loose even with it having an automatic belt tensioner
The seat belt might not fasten in a 2000 Chevy Blazer because there is a foreign object in the slot where the seat belt fits. Even the tiniest of objects can cause the seat belt to not latch properly.
Because the alternator puts a load on the engine of several horsepower, the belt must be very tight. However, if it is too tight, the bearings of the alternator shaft will wear out quickly. To tension the belt properly, adjust until there is about 1/2 inch of play in the center of the longest span. If this does not stop the squealing, the belt may have been glazed from being too loose, and needs to be replaced.
There is also a possibility that an idler bearing has failed but that noise is a bit different from a rubber on metal squealling noise. To be certain of the problem befor you start throwing parts at it is to remove the belt and check each pulley and idler pulley (on the tensioner) for excessive play and/or rough or lumpy feel when you rotate them by hand.
The belts are not aligned correctly, or something is bent; pulley, bracket, look and see . The belt should look straight.
Check the fan belt it may be tight when cold and causes the whistle until it loosends up when it warms up during use. Can also be caused by the throttle body needing to be cleaned, carbon build up on the IAC motor
NO it won't even bolt up to it. Chevy REDESIGNED THE ENGINE BLOCK AND TRANSMISSION BELLHOUSINGS in late 1999.
Check the tensioner and make sure it has the correct tension on the serpentine belt. Even with the proper tension, sometimes the belt will still squeal if it is older, after several years of use, especially if you live in a very hot climate, the belt can "glaze" and become slick. Hope it helps...JC
An old or worn serpentine belt will cause squeaking on startup, particularly on cold days. You may first want ot try a $3 can of "belt dressing". This makes the belt and pulleys stickey and and will resolve most squealing. If it persists or gets worse replace serpentine belt for around $35. You may need a wrench which you can borrow form most parts stores. You should have a small diagram showing the path of the belt under the hood near the front. It the squealing pesists, it might also be caused by failing belt tensioner (one of the pulleys that keeps the belt tight, $50). If it persists, then look for more serious problems such as a failing bearings in ac compressor (strange clanking or clicking even if the ac still works (take it to a pro)) or alternator (usually accompanied by a dead battery or electrical problems (DIY for around $150)), or even a failing clutch in ac compressor or fan (long shot if you ask me)).