loud squealing/screeching noise 98 3.8L

I have a loud squealing noise coming from the rotational area on 3.8L. It started after I changed the belt, alt, and powersteering pump. The car has been sitting for about 3 months. I changed the belt tensioner and pully and the idle pully. Still loud under engine excelleration. Only thing left is the AC and the water pump. They both spin freely. No noise running the engine without the belt. I'm worried it's the main bearing. Any thoughts? I'm hoping it just the water pump at this point. Water pump doesn't leak a drop. Comments.

Thanks.

Good chance you may have a wrong size belt. I know you most likley told them the year and make but sometimes they run larger than spec. The other option is somthing in the belt area is worn out and causing the belt to slip.Not sure on the 98 but I thought It was one main belt for all AC, water pump, alt. power steering. If this were the case if your AC is not working it most likley the problem. But some were along the line the belt is slipping. If its only on acceleration to me sounds like the wrong size belt.. I have a number of times have had wrong size belts. Had to buy from the dealer or NAPA.Make sure there is no oil or fluid around the belt area.

Wow! you were right. Replaced the recommend belt with a smaller one and ALL is perfect! Thanks so much. I've been chasing this thing for months.

They list 2 belt sizes for my '96 3.8L at Autozone.
They said that they are very close in size.
I stumbled across a TSB on Alldata that may explain the 2 different belt sizes.
There was a issue with the A/C making a groaning sound after the vehicle has been driven for a while in HOT weather.
This was caused by some resonant frequency with the A/C and other items..... So the solution was to replace the A/C pulley with one that is slightly larger in diameter. So, logic would suggest that a slightly larger serpentine belt would be needed.
Being a TSB, this change of pulley size would only be done if you went to the dealer with a complaint of the A/C making a groaning sound in hot weather.
Otherwise, you have the regular pulley.....and need the smaller belt....if this is the reason for the 2 sizes.

I Like Auto zone. But I have most of the wrong sizes come from them. I work for Good year which also makes the Kelly belts that some Autozones also carry. But I only work for the tire plant. But have heard of some spec issues with the Kelly belts. Some older cars are more forgiven when it comes to belts, mostly
the one you adjust your self. But on the serpentine belt some will slip if not the exact size or slip after a short time later after the belt wears a little. Dont get me wrong I have some good belts come from Autozone.. But when it comes to changing the surpentine belts I buy from Napa and if a problem occurs from them
I go to the dealer. Just less of a headache for me. Glad for knowledge on the TSB pully change. I can keep that in mind wisewind.. Glad you got your belt problem solved Fchanes.. Gary