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paulv · 11-23-2010, 05:59 AM

I have an '07 Box with the OEM battery, and starting in '09 I began measuring the battery cells (specific gravity and charge level) with a precision refractometer. In May '09 (~25K miles), the average cell measurement was 1.300. For Oct '10 (~41K miles), the average measurement has fallen to 1.265. For a good battery, each cell should be 1.260 or better. As others have said, four years looks like the limit for an OEM battery, and that's the direction my battery seems to be going!

Regards,
paul...

11-23-2010, 05:59 AM	#9
paulv Registered User Join Date: Apr 2006 Location: Boston, MA Posts: 221	battery measurements I have an '07 Box with the OEM battery, and starting in '09 I began measuring the battery cells (specific gravity and charge level) with a precision refractometer. In May '09 (~25K miles), the average cell measurement was 1.300. For Oct '10 (~41K miles), the average measurement has fallen to 1.265. For a good battery, each cell should be 1.260 or better. As others have said, four years looks like the limit for an OEM battery, and that's the direction my battery seems to be going! Regards, paul...