What you are hearing is the serpentine belt tensioner going bad. Cheap and easy to replace. Replace the idler pulley at the same time to avoid further headaches, also cheap and easy. Don't bother just replacing the bearings, they cost almost the same.
Don't re-use the belt, it's been damaged by now even if it looks fine.
BTW- SOME 3.0's only had a idler pulley, but by 1995 im fairly sure it had a tensioner as well. The later 3.3, 3.8 etc. all had the same issues with idler pulleys. The Aftermarket parts by quality brands like Gates eliminate this in most cases and are far less expensive than O.E.M. parts.