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I must confirm the same experience. Years ago I bought a set of surplus 6TL army batteries from a surplus dealer for $ 60/piece and they lasted almost 6 years without any problems. Then I bought a set from Interstate. Two years later, they were toast. No warranty of course, because their lousy warranty is 6 months free replacement, and 6 months after that pro rated, for a lousy 1 year warranty. The next set from them was even worse. One of the batteries dropped a cell after 12 months and they would do absolutely nothing about it. I had to fight just to get a 10% discount on a new battery. At $ 150/ piece they are no bargain for sure.I will never buy another Interstate or NAPA for my own stuff ever again. We have have about a 70 batteries in logging equipment, trucks, tractors and buses. Strong Box and Hibernator from John Deere are the best. They will honor the warranty. Interstate will screw you every time, 13 months and you pay a steep pro rate and your still stuck with a crap battery that you get replace again in 13 months. Same with NAPA. I just put two Wal-Mart Batteries in my Deuce, three year free replacement $80 ea. Modified the hold down and made a longer center cable.