My battery and emer. brake light stay on after my truck is started, and sometimes it takes a few times for my truck to start. My battery Gage is really low, my temp. Gage stays under normal, my windshield wipers are unusually slow and my radio will sometimes turn off like my battery isn't staying charged. It's never had a problem with corrosion until now and I cleaned it off and checked electrolytes and wiring.After I come to a stop my truck lacks power until I get to third gear and then it's fine. What could this be? Please help!