I'm not seeing anything regarding batteries. Mine has had a Diehard International 31248 but it seems it's bitten the dust. What's anyones experience? Sears does not have a series 48 to ship unless its AGM, which is 209.99, twenty more than the lead acid 48 they don't have. Anyone use an AGM? Would it need the vent as on my old lead acid? Any other brand recommendations? The car is a 1997 4 cylinder sweetheart.