Did just that because I wanted to know what the problem was. They say the alt is putting out only 30 amps and that the battery is accepting a charge. He did notice that my idle was a bit low and the terminals were a mucked up. So I bumped the idle a bit and cleaned the terminals up all nice and shiny!! I'm glad to hear that it's as simple as replacing the brushes. I'm sure they need replacing, I'm just hoping the battery holds out with a lagging alt.