The voltage regulator is in the alternator. I found that overcharging can also be caused by old oily brushes in the alternator and the voltage regulator can be fine. If you are really handy you can replace the voltage regulator yourself. But if you need to keep your truck in service, I would pull an alternator at a junkyard, get it tested, and then put it in. You can take your old alternator to a rebuild shop to be properly cleaned and diagnosed. Sent from my SM-N950U using Tapatalk
    • Like