When to replace 6v batteries

wantabe351 wrote:
When testing my 5er 6v batteries,I charge them for 12hrs on my home Battery charger,then disconnect them..the surface voltage is 12.8v after 4hrs its down to 12.5 and after 8hrs it sits at 12.2 for 2days..using my hydrometer the cells are just above or in the replace zone..the Batteries are only 5yr old and no mater how long I charge them or do a 14.5 voltage charge, the voltage after a day drops to 12.2v disconnected. is it time for new batteries

There is a lot being unsaid there. How could the batteries be so bad at five years and not be noticed as being almost that bad two years ago? This did not happen in the last few months.

I suspect the OP got the four 6s years ago with off-grid in mind, but never used them and they sat at 13.6 ever since, so here we are. IMO unless there is a change of RVing style, just get one sealed 12v batt as replacement and replace that every year or two. Save money and not have to do battery maintenance.