I have read a couple of threads on this and I really didn't understand. Several people have had a squealing sound when going in reverse, and I just started experiencing this a few days ago. I have not looked at it yet and plan on doing so tomorrow. Everything was fine until I replaced my power steering pump. When I drive normal is everything is fine, but as soon as I go in reverse in squeals for about 3 seconds. It's definitely coming from under the hood. My question is, if the belt is to tight or loose it will squeal no matter what and not just in reverse, right? Same for the P/S pump if it's bad then it's bad.