I got about 10 yrs. out of my first pair of Odyssey (originally Black Panther brand) batteries. I swapped those out for a pair of identical sized Odyssey batteries and those have been in the truck about 4 yrs. now:
- http://www.4crawler.com/4x4/CheapTricks/DualBatteries.shtml

Not sure if having dual batteries helps with life time, but those batteries are designed to last up to 12 yrs. I periodically swap connection between my main and aux. battery but most of the time they are both hooked up in parallel.

r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
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