I too experienced this issue with my 2017 Silverado LT 4x4 after replacing my dead battery. I had thought that maybe the battery was incorrectly installed but after careful checking it was not. The voltage fluctuations being read on the meter on the dash would fall short of 12 volts. I took the alternator into O'Reily's Auto Parts and had it tested. 3 out of 8 tests showed a fault with the voltage regulator so I replaced the alternator for some sense of security and not being left stranded with a possible dead battery. I also replaced the belt and tensioner since it is now a 5 year old truck. With a whole new set up, I'm still seeing the volt meter dip to 12 volts. Should I have replaced that expensive alternator after all?
