I have a group 29 Interstate battery that I bought in may 2001,and I believe it it shot already.I keep it on a good float charger in the winter,but I thought that I would get more from this battery.My dad has a older Interstate battery in a old truck that never gets drove,and it lasted like 8 years.<br /> The fluid was a bit low this spring,but I topped it off with didtilled,charged,but it deems very weak.Any and all info much appreciated.