I would get the battery that is bubbling and has an order coming from it tested. That usually indicates a bad battery. I keep mine plugged in all the time and have not had a problem, just keep an eye on the water level about every 4 to 6 weeks
2007 Ford F250 Super Duty Crewcab PSD
2007 KZ Durango 285RL 5ver
Bubbling battery is probably either weak or has a shorted cell.
Time for at least one battery.
Check the float voltage and post the make/model of the converter for better info.
2001 F150 SuperCrew 5.4 Lariat Offroad 4x4 Tow Package 4.10 Truetrac
2006 Keystone Springdale 249FWBHLS
12K SuperGlide, KGE3000Ti 2.3kw rated 2.6kw max
Frank's voltage booster, Prosine 1800 powered by 4 GC2 batteries
Outback should have a WFCO if a 2006 model. Always recharge batteries fully before storage to maximize lifetime. Batteries will out-gas and require periodic addition of distilled water -even with a three stage charger like the WFCO. Especially if deeply discharged before charging. You have some indications of a failing battery. Sounds like a load test is in order after fully charging.
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