T660 electrical gremlins after batteries changed

Friday we changed all 4 batteries after checking that 2 were bad, and had slight leaks. This morning while deadheading to my shipper everything was fine, i shutdown to get loaded, then started the truck to pull forward and my voltmeter on the dash was reading 16.3volts. I informed my company shop, they said to run with it till i shutdown for the night and call them to have someone come check it out. I dont even get 2 miles away and i lose all my dash lights, headlights, turn signals, speedo, and tachometer. I pull off and check all my alternator and batteries and everything is tight. I restart the truck and everything is lit back up and working fine, except for my voltmeter on the dash. Driving another 5 miles and the same thing happens. Lost everything on the dash and no outside lights. Shop decides that i should drop my trailer and head to the kw dealer on the north side of lima oh.

Interesting tidbit....
As i bobtail over to the dealer, the voltmeter is reading 14.1v and the lights and all are working....im at a loss and so is my shop, hopefully this kw dealer can make heads or tails

 

Got over here to the shop and the shop here says that the alternator (which is on only 3 months old) is the problem. Not sure what is wrong as they spoke with my manager. They did check all the connections, and couldnt find anything till they tried testing the alternator under a load, then they started to hear "noise" from inside the alternator body

 

And that was exactly what was happening. After the swap i was able to run for another hour and a half before shutting down and didnt have an issue at all.