I have a problem where the battery repeatedly drains even though the alternator is fine and apparently that battery is ok . Seemed to be a ground issue and replaced the bolt for the terminal and it ran fine for a while and then died. By the the way the volt meter wasn't reading anything while it was running fine and driving around. I hear there can be some sort of volt regulator that can go out? I am just having trouble diagnosing this and was seeing if anyone could help with some insight. Perhaps you have had a similar situaion?

 

And if it helps any extra the truck jumps just fine and runs fine once you charge the battery. Just seems something other than the alternator is keeping it from sharing. It runs for about 10 miles or more on a charge.