What research? From who? Show me another battery that'll last 7 years in an off-road truck with high load and harsh conditions, and extended drained periods.

That's a long life for a battery but doesn't beat 13 years form my original BMW battery in my M3. :) I think it latest that long because I have it attached to battery maintainer most of the time.

Anyone have experience or comment on AGM batteries?

The battery I removed from my 2006 X5 last month (Dec 2014) clearly had a mfg date from 2006. So, the OEM battery lasted 9 years, when it finally died.

I was just doing research for what batteries are considered better or the best for our e53's and my research ended up being more broad to batteries and warranty adn experiences in any vehicle. Anyhow a LOT of forums (pirate4x4 included) have negative reviews of Optima batts and other options are more accessible/smarter/cheaper cost than the brand name Optima.
To me it seems Optima is living off their name they MADE (just like Apple) and now that the rest of technology has caught up with them and perhaps even surpassed in a few qualities, its now nothing special to have an optima as a power source.

Not trying to offend you personally, but my factory BMW batt lasted almost 10 years and thats with LOTS of daily SHORT trips in stop and go traffic. Probably a more harsh environment than what an offroad truck goes through (battery wise). I'd assume most offroaders are not daily drivers and therefore subjected to different power requirements and the frequency of them is less than a daily driver.
Anyhow, if you like Optima, then go nuts. I just found a better solution for MY needs.

PS: should not really be comparing AGM to non-AGM batteries either tho, to keep it equal in comparisons...

I can also attest to Optima's decline over the last 3-5 years. They used to be a really good battery to have. I think they got bought about 5 years ago, if memory serves, and their quality has drastically declined under the new owners. I did this research a long time ago though so I can't remember any specifics... but I think most agree now that Optima is just a name now...

I will be looking into an AGM battery replacement for the X. Nothing wrong with the current batter that's in it (from 09) yet, but I want an AGM in it after this one goes. Will be reviewing this thread in it's entirety then.

FYI: picked up a Bosch 900 CCA 185RC at pep boys just now for $125. 30% off 150 and I did the swap there so they deducted the core charge. Not AGM but it'll work just fine.

just doing the MTP-95R install now in my 4.4i and im running into a small space issue. the class 49 batt that is in the black tub is secured in place by a few tall wedges... i put my class 95 batt in and these wedges seem to be inhibiting my batt install.
This MTP-95r is the same exact size as the duralast gold and people seem to be running this but is anyone running it in a non 4.8iS?
Maybe a 4.8 can handle the 39cm battery but not a 4.4 :(

I'm sticking with

WSO EXACT FIT BATTERIES - WORLD SOURCEONE®

Does Exide make Boshe batteries?

Looking at the specs, it looks exactly like Exide's:

http://www.pepboys.com/product/details/672418/01063

I don't know who makes the battery for Bosch.

Since my 1998 Volvo S70 battery is basically the same as my 1998 BMW 528i or 2006 BMW X5 3.0, the Exide L3/48X battery should fit the E53 nicely, for a much better price of $94, as I hate paying $130-$150 for the Autozone junk battery.

So, this is what I use now, time will tell how long it lasts. For those with tight budget, this EXIDE battery is cheaper than Autozone, and maybe better. Photos of the Exide battery in my 1998 Volvo S70:


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