It seems as if I can't get the batteries (both engine& house) won't last but just little over a year..I try to maintain them,water,running the engine , etc, but now I need 3...in looking at the dates ...
My U-2200s just died at 8.5,, My Chassis battery is .... Very close to dead I think.. I"m hoping it will last the month with help. (Same age)
My G-31 AGM's barley made it five years. (And folks tell me they should last longer) and I've had Maintenance free (My chassis battery) several that made it to the 9 year point.
So if you are killing them in just a year, You are either seriously OVER charging them (Any time) or seriously UNDER chargeing them over-winter.