My first house batteries(2 6v deep cycle Interstate Workhorse) lasted 14 years with proper maintenance and a smart charge system. The present ones (Duracell golf cart 6v) are 4 years old and still ok. The chassis battery is a different story. Since it is a "maintenance free", I cannot check levels and properly look after it . Cleaning and maintaining a good charge has helped, so I'm only on the third one in 18 years. It is five years old and beginning to drag a little at start and will run down when I leave the auto step on. I guess it's time for another five year battery.
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