I have followed this thread with great interest. ?It took a too familiar path. ?I felt there wasn't enough info (in the initial post) for me to respond and (given my slow and limited? typing skills) assumed that someone else would ask the right questions and come up with the best answer.? As usual, they eventually did.
I found it interesting, but all too typical, that the first responders made a flat recommendation to "replace them all " without asking the age of the current batteries or inquiring as to exactly how the one battery failed. ?Shorted cell? ?Open cell? Weak? etc?
I understand that none of us learns anything from (maybe YES - maybe NO) answers, but often we are to eager to quote the Party Line or cookie cutter answer with minimum ?knowledge of the facts. ?Often, (it depends....) is the best approach to an answer.
Hugh did state, in his second post, that the batteries were only two years old and that certain anomalies had existed for some time. ?That additional information inspired some well thought-out, logical and somefrom experience answers to quickly follow. ?However, Hugh had already replaced three expensive, two year old, batteries that likely had several years of life left in them. ?Maybe yes, maybe no - LOL.
I do understand the logic of replacing all old tires and allold batteries, but I also know that (unlike tires) it makes only good business sense to squeeze as much useful life from a battery as possible.? Batteries are seldom a life or death or safety issue.
Enough philosophy, but I was just wondering......
I have a burned out overhead light bulb... ?should I replace them all? ?How about that one foggy window... do I replace them all?? LOL
FWIW my 2 cents....
BTW - my first (and only) factory job was assembling batteries in Chicago Heights, Ill, at a Gould National Battery plant.? My job was to put the three bakelite cell covers (all automobile batteries were 6volt back then) in place and seal them with melted rubber so the next station on the line could put those two lead straps in place.? The job payed $1.25 an hour.? I quit and joined the US Navy.? They paid $.14 an hour.