even a new battery if run dead dead, can ruin its cells and NEVER again recover
if you have a volt meter
charge to full charge, and test and see what its at volt wise
wait a few hrs and test again and see if its dropping on you
same can be said, on HOW you re charged the battery, some require LOW amp re charge and if you DODN"T do so, you could have cooked the cells in the battery , thus ruining it
having load tested will answer this too, and best bet!
Just got back from warrantying a battery I bought about 3 weeks ago all was good had it in the shop put it on trickle, click click click, take all cables apart to clean to find out yes the battery won't load test. Shows 13v prior to test, this was not the cheap battery either, I spent the money on ultra. Thanks for warranties, funny thing is there was nothing wrong with the old one I was just being proactive.
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