Take the battery to your local auto parts store and let them test it. But I think he is right, it is probably toast. I keep some battery acid on hand to put in the thirsty batteries annually as well. You might know this already, but I didnt know it so Ill share. On a side note, remember that if your batteries drain beyond a certain point, they wont charge back up using the on board multi-bank chargers. You have to use a conventional charger to bring them up some.
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