Hello! Wondering if someone could help me with a head scratcher? I have a 2006 F150 5.4L 4x4 XLT with 317,000ish KM on it. My problem is that over that past 2 years or so I have had alternator issues stemming from overcharging to undercharging. It all started after I replaced the original alternator after about 9 years of service. Absolutely no problems. So I replaced that one with a dixie brand alternator from a local jobber store. after about a month it the voltage would fluctuate from 14.5 down to 12.5 then down to 11.5 and then back up. It was very sporadic at times with periods of no issues back to undercharging. I took that one back to the jobber store and they tested it and it was a defective alternator that wasn't putting out enough volts. I bought a ford reman alternator next and that one lasted about 9 months before it started having issues. My headlights lights would flicker and my dash and interior lights would also. So off to buy another alternator. About two months I bought a AC delco alternator with lifetime warranty. Just two days ago the alternator would surge up to 15.7 volts and my l/h rear abs would start coming on for the same amount of time that the alternator would be overcharging(about 5-10 seconds)and then go back down to 14.3 for a while and then back up to over charging. It was very sporadic. My headlights lights would get very bright and my dash lights would also. And thats where I am at today. My battery has never been an issue and at no time have I not been able to start my truck. I also changed the harness that goes from battery post to the starter and the jumper harness that goes from the alternator and connects to the starter/battery harness. Please help and if you need any more info just let me know. Thanks in advance