My '95 Dodge Cummins needs new batteries. After 9 years of faithful service, the blue top group 31 Optima are starting to slow down. So I'm looking to replace them. I like the long service life and zero problems and corrosion issues they've given me. I'm thinking I can stay with the same ones. The group 31 batteries just barely fit in their respective trays. The terminals are pretty close to the hood. Since I don't use the truck for snow plowing anymore, I'm thinking I could save some bucks and get the smaller group 27 batteries. They are the same size only shorter and lose only about 100 cca's each. The other part of me says it worked for 9 years without issues, why change the formula?
BTW, the blue top marine group 27 and 31 are electrically the same as the other Optima group 27 and 31 batteries. I've used the extra 5/16"s screw terminals for extra electrical accessories.
What say you guys? Same size? Smaller? Perhaps you have a recommendation for a different brand? It has to be a sealed AGM or the like to be considered a contender to be bought and installed. I don't use the truck very much and don't want the issues associated with traditional lead-acid batteries.