Alternator acting weird...
I have an issue with my alternator. I have a 03 6.0 CC 4x4 SRW with a single alternator. For what I have read, its a stock 100 amps. I use my truck every 9 days for 5 days. So its sitting for 9 days. there is a rproblem with battery drain, so I leave the bateries disconected. The problem is that my Edge CTS shows that when I ran the truck, sometimes it reads 12.6-12.8V and after a while, or the next day, It reads no more than 13.8V, and always oscillating, even if I drive at 2000rpm steady for a couple of hours. I´ve been told that the brushes 8carbon things) may have wear out, or that I may have some oxidation in the alternator rotor. Any Idea what how to fix this? My truck has 262.000 kms...162K miles.