I'm going from a 24V trolling motor to a 36V one. Last year while I was on a spring fishing trip, one of the batteries for my trolling motor went bad. I decided to just replace both batteries since I wasn't sure how old they were and didn't want the other one suddenly giving out too. I was in a small town and bought two new batteries from a Napa store. They are a no-name battery. My question is, when purchasing a new battery to go along with those other two to complete the 36V series, does it matter if they are different with regards to battery size or cranking/reserve amps? Do I need to try and buy a battery that is as close to the other two as possible? Thanks