I guess your not using a tender I get 6 or 7 years out of my batteries but use a tender.

 

Stock batteries on our 07 and 08 UCs lasted slightly over five years and replaced with stock ones in 2012 and 2013 expecting to change out in 2017 and 2018 no complaint about Harley batteries. May be I'm lucky my SUV lasted 6 years and wife's 2006 Benz still have original factory battery so I'm sticking with that one too know it's costly but reliability is way more important.

 

I have an interstate battery which I installed in 2009 and have not had any issues with it. I use a tender all winter. I will replace again next spring since I feel 6 years is long enough. Also had the factory HD battery for 6 years with zero issues.

 

like one said east penn makes the oem battery and they have stickers that say another brand name on them. bought mine from batteries + and there were other stickers in the box so it could be changed. don't remember all the different names but one was decka i think or something like that. been alot of talk about this subject. good luck.
kroozeabout.

 

Yes tender used last 3 years I've owned bike can't speak as to be for that tho