Just some info that I hope may help someone else out there. My son has a 2005 4.0L explorer. He was complaining about a squeal that he thought was the fan belt. The belt was riding on a plastic part of the dampener but was in correct alignment with the other pulleys. I couldn't tell whether the belt runs on a plastic pulley with a steel pulley behind it that is not used but can come loose and move forward to squeeze the belt out of its grooves or if the steel pulley came loose and moved rearward out of alignment with the other pulleys and the belt slipped down on to the plastic part of the dampener that the steel pulley used to be mounted on. We replaced the dampener and all is now fine.

The dampener for this application has been redesigned from the original and the Ford part numbers have been superseded several times so they know a problem exists but they won't admit it. Searching the internet produces other people with this problem that paid anywhere from $750.00 to $1300.00 to repair this. Thankfully we figured it out ourselves and fixed it with a $197.00 modified replacement dampener. Has anyone out there had a similar problem?