Charging problem

[Smokin751]

My alternator wasn't charging. I changed it. Looked good, the battery light went out and started up. Drove it the next day and after it warmed up and around 2000 rpm the radio shut off and the gauges froze and reset. Tested the voltage at the batteries. 13.8 at idle then reved to 2200 and it went up to 16.0. Should I change the alternator again or is there another problem I should look for? It's a 2003 F350 with a 6.0.

[808xon]

Have you checked the batteries, if over charging the stock batteries , they will leak.