2008 E88 battery NEED HELP!!

[oneprettybeast]

im not sure which battery [OEM] I need for this car, I have a intersate currently in there {I didn't put it in}. I need the proper battery to put in tried calling parts and services and they aren't even sure which one it is,, I have a convertible, n54, M sport package 6MT, premium package.. anyone with this same setup that can help me with the proper battery? would be greatly appreciated!!!

[JimD]

Originally Posted by beamerkid1

im not sure which battery [OEM] I need for this car, I have a intersate currently in there {I didn't put it in}. I need the proper battery to put in tried calling parts and services and they aren't even sure which one it is,, I have a convertible, n54, M sport package 6MT, premium package.. anyone with this same setup that can help me with the proper battery? would be greatly appreciated!!!

I looked at RealOEM but it lists BMW part numbers, not part numbers for the battery company. There were several exide batteries listed for my car so I looked on their website. They list more than 10 batteries for my e88 (2009).

I think the bottom line is a lot of batteries will work, but you need to decide how you want to do this. The prices shown on RealOEM were not terrible, generally about $125. If you can get a batter at the dealership for that, you won't save a whole lot by going elsewhere. Putting it in doesn't look too bad but then you need coding. If you want to simplify the coding you need to know the amp hours of your current battery. It is in the car's current programming if you have the ability to read that (like using NCSExpert). But if you can read it, you can change it.

You may also want to relate cold cranking amps to amp hours. BMW uses amp hours to decide how to charge your battery but batteries are sold emphasizing cold cranking amps. Unfortunately they are not related directly. But reserve capacity, which is often available with a little digging, is. If you multiple the reserve capacity by 0.417 you get amp hours. I took a look at the exide batteries listed for my car. The 900 CCA batteries were all 185 reserve capacity and thus 77 amp hours. The 800s, however, were either 140 or 170 reserve capacity and thus 58 or 71 amp hours. 850 CCA batteries were all 67 amp hours. 720CCA and a 760CCA were 50 amp hours. So it is a little variable but clearly lower CCA = lower amp hours even if the relationship isn't direct. (cold cranking amps is a measure of the battery to generate a lot of amps at low temperature. reserve capacity is the number of hours a battery can generate 25 amps.)