Chevrolet Repair: Squealing around alternator., chevy tracker, pullys

Question
Hi,
My son owns a 96 Chevy Tracker. My husband and son has changed the alternator twice and the belt at least 4 times in the past 3-4 months.  It squeals when it is first started and until it gets to about 3500 rpm it quites.  The belt is tighted to 1/4" of movement (being able to push down on the belt).  The pullys have been cleaned and checked for allignment and all are straight.  Belt dressing has been applied to the belt a few times with no help to the squealing.  The water pump is also on this belt.  The pully for it has also been cleaned and checked for allignment.  My husband checked to make sure it moved freely like it should and it did.  The water pump wasn't replaced because it seems to work fine.
We are at a loss as to why this is still squealling.  Is there anything that you can suggest?

Thank you,
Brenda

Answer
Remove the belt and spin each pulley by hand and see if a squeaking is heard, if so change the part that makes the noise, also you may want to look into the belt tensioner? if it is not putting the correct amount of tension on the belt it will squeal