[Aaronm206]

first off, If this has been answered, Im sorry and would love a link to that thread. I have seen a lot of "Battery" posts but haven't found one to answer the question of how to find out what battery came in my car originally. It seems that these cars are very sensitive when it comes to electrical things. I have a 2008 335i E90 that I bought used. The battery is failing and Im not sure the battery that is in the car is correct and Id like to go back to what came in the car. How do I find that info? If it was a H6, H7, H8 etc. It seems they came with different batteries and I cant just get a "BMW 335i battery". If I cant find out what battery came in the car, can I just get a battery the says it will work for my car (from auto parts store) and code and register that? How exact a match do i need to the factory battery.

[Bims328i]

A scanner can tell you what battery type and AH capacity is currently registered.

[lordnikon]

Stating the obvious. Can't you go and physically check the battery?

[jsunma]

I think/guess what the OP is saying is that he wants to know what battery the car came from the factory with when new, and that whatever is in the car now isn't a BMW-branded OEM battery.

My suggestion would be to take your car to the dealer and go to the parts counter with your VIN. Have them look it up. That will either get you very close if not exact info on what the car came with originally.

For what it's worth, you may find that purchasing that BMW-branded battery (whatever they say you should buy) is an entirely cost-effective option as in my experience, batteries are one of the few things that dealer parts departments have reasonably-priced. I've bought both of my replacement batteries from the dealer, and I wouldn't have done better purchasing a similar battery anywhere else.

OP will want to be able to register the battery properly once he gets it, assuming that it has different specs than whatever is being replaced.

[lookalikehuuh]

Who cares what battery it came with from factory. I recommend getting an H8 AGM battery from a good manufacturer. A H8 will give you the maximum supported battery size in the battery box of your car's trunk. It won't neede maintenance and won't suffer from potential acid leaks like a flooded battery can.

I upgraded my cars to AGM H8s years ago, coded the car to know that it now has AGMs and haven't looked back since.

[Daaaaaaaan]

While I’m sure part of the variance has to do with supply at the time of manufacturing, I think they’ve tended to ensure the bigger batteries were installed in colder climates and sometimes putting in smaller batteries in warmer climates. In cold weather, you’ll be in more situations where the extra current flow will give you a successful state.

Bigger battery of course means a bit more weight and a bit poorer fuel economy (but shorter interval between death and replacement)

[Canuck335]

Battery specifications and manufacturers change over the life of a car, and even during the production run.
You can get an idea of what was originally used via realoem
https://www.realoem.com/bmw/enUS/sho...diagId=61_1999

But as others have said, contact your dealer with your VIN and they will tell you the latest and greatest spec for your car and operating conditions.

[Captain Buumer]

Because car batteries are universal parts that fit all of the cars.

36% of them are made by one company - Johnson Controls.

Distributors put their own logo on it and ask money depending on how famous the brand name is.

Good example is Varta or Bosch that are exact same items with different logos and different prices.

My 2007 car originally had Lead Acid 75aH Varta battery with BMW logo on it.

Obviously it makes sense not to get the original one because bigger 95Ah fits in the battery tray and AGM type is much better suited for cold climates.

[TheMidnightNarwhal]

Originally Posted by lordnikon

Stating the obvious. Can't you go and physically check the battery?

Yes but it's a PITA, most times the distribution box covers all the labels.

[dav9515]

it really should be easier

[lordnikon]

Originally Posted by TheMidnightNarwhal

Yes but it's a PITA, most times the distribution box covers all the labels.

Been there, done that lol

[mainbearing]

+1 on H8 ~90Ah AGM battery. Code it or make sure its 90Ah and register the new battery.

Have a Costco Interstate now. BMW did a poor job with the spaghetti wiring in the battery compartment that gets in the way.

https://costco.interstatebatteries.c...option=2364365

[StradaRedlands]

Originally Posted by mainbearing

+1 on H8 ~90Ah AGM battery. Code it or make sure its 90Ah and register the new battery.

Have a Costco Interstate now. BMW did a poor job with the spaghetti wiring in the battery compartment that gets in the way.

https://costco.interstatebatteries.c...option=2364365

That's what I used for replacement recently. It better last a long time, as fitting a H8 in there is a chore!!!