S Davis wrote:
That is not true on newer GM HD trucks, my 2019 Chevy 2500HD sits above 14 volts, when changing my batteries it will ramp up to just above 15 volts @ 50amps.
According to the above statement I should have a smart alternator, but I have yet to see this mysterious lowering of voltage a few people on here keep stating.
Check the voltage at the starting battery immediately after starting and at the house battery.
Drive for 10-15 minutes and, with the engine still running, check those voltages again.