So I replaced my alternator today. The battery light and Power System Service message was becoming more regular. Dash Command was reporting a system voltage of 12.8V when running and the power message. The voltage had a lot of fluctuation between 13.2 and 13.8V otherwise.

It was all going fairly smooth until I was tightening the top alternator bolt. It was about half way in when it got tight. I applied a little more force but not too much and the dang bolt snapped... Aaaaaagggggg!

I measured and found that the bolt snapped protruding out from the bracket about 1/4". It might have been enough to stabilize the top and rely on the two lower bolts. However, if it wasn't enough, I would be screwed (pardon the pun). I decided to do the right thing, remove the alternator and extract the broken bolt. Unfortunately, the bolt was locked hard. Must have been a bur in the threads. Fortunately, the alternator bolts to a removable bracket. I drilled out the bolt and used a 3" bolt, split washer, nut and thread lock.

The reman Denso alternator from FCP Euro is working great. The system voltage is rock solid so far.