Unfortunately I had ignored the squealing noise for at least several months before it finally started to exhibit charging issues. It was FordMan59 who clued me in on replacing the alternator brushes at around 220 or 230k. I found that the old worn brushes had severely damaged one of the commutator. http://www.bing.com/images/search?q=commutator&qs=n&form=QBILPG&pq=commutator&sc=8-9&sp=-1&sk= So after replacing the brushes as FordMan59 had suggested, only got another 20k or so out of it. Had I not ignored the squealing noise, would still be running on that OEM. The alternator that replaced the OEM lasted 1-2 years; cooked itself quite well. (fortunately maintained the normal 14.4v and below output until it quit) This was an alternator purchased from NAPA, lifetime warranty, Motorcraft casing, rebuilt by Raybestos. Upon initial return was told they no longer stock or deal with Raybestos and would have to wait a week or two for the old alternator to be shipped-out in exchange with them. Not willing to wait that long, asked for a refund and was denied. Went and got an alternator from CarQuest and it seems to be of excellent build quality. It came with detailed documentation, including spec-by-spec test result numbers. It was definitely a lot heavier than the Raybestos crapola. Maybe a week after installing the CarQuest alternator, went back to NAPA, told'em I couldn't wait and had already installed an alternator from elsewhere; again asked for a refund. The second time they granted it! It is an independently owned shop and was purely at the manager's discretion.