Any battery that has a pro-rated warranty is designed to fail before that warranty is up. It brings the customer back in for what amounts to a minor discount on the price of a new battery.

It is relatively easy for battery manufacturers to design to a specific life. To me, anything after five years is borrowed time, and I would replace it, due to the inconvenience of a failure when you least need it.

Any car can use an AGM battery. The E53 did come with an AGM in europe.
I am well aware of warranties and pro-rating. The point I am making is that if you are changing batteries every 2 years something is wrong, or you live in Croatia apparently.

Thanks for all the feedback guys! Yes, Ive been driving the X since end of Feb and only on weekends. Still cranks up every time I start it. My uncle told me it's still the original battery when he bought it. Ive read that batterires usually last for 4-6 yrs. Battery's is almost on its 6th yr life. Its an easy DIY thanks to this forum. Dilemna: Dont want to get stranded on a weekend road trip. But, I would like to know if my battery will still make it till next year after storing my X this coming winter. I should get it load tested later & make my decision. Cheers all!

This is exactly everyone's point except some still don't get it. My 3 year or less interval was an example...and it's an interval where it's the owner's preference; also depending on climate and usage.

Yes, we are agreeing.

I worked in a garage years back, and we sold 36, 48, and 60 month batteries. They regularly failed at 34, 46, and 58 months. The customer with the most expensive battery would come in with a failure at 58 months, and get 2/60ths off the price of a new one. He invariably felt like he put one over on the battery company, that he had won something, as he got to claim on the warranty. To us, it amounted to a 3% discount on a battery sale. We didn't even claim it off the battery company, it wasn't worth the paperwork. Incredible how the battery companies could calculate deposition rates and get them to short out just before the warranty sticker ran out. Yes, running batteries very low, or brutally cold winters, could affect the failure date, but the percentage that failed just before the warranty was up was incredible.

Verdict: I bought a new Duralast Gold battery ealier today @ Autozone for $130+. Did the simple DIY and X5 runs good. The computer reset itself after driving it. I have em load test the BMW original battery and the results - 12.6 volts & 1.9 amps. still a Good Battery. Surprising knowing its 6 yrs old. Oh well.

Money well spent? :dunno: :rolleyes:

Piece of mind well spent.

Exactly. After six years, it doesn't owe you anything.

Photo of battery location?
 

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