2006 Dodge Ram 2500 - Charging System Problem

I cant get the truck to charge my batteries,I put new batteries in it , put a new alternator in it still nothing

You told us almost nothing about your truck or how you disgnosed a bad alternator.

What engine? Mileage?

What voltage does the alternator put out when the truck is running? Battery voltage when the truck is off? What is the field wire voltage to the alternator?