Originally Posted by e92zero
hmm, I just want to learn more about the battery. Fsarc indicated that the Deka battery is exactly the same but the ah rate of the Deka is at 95 with a cca of 850. Isn't the oem battery at 90ah and 900 cca? Does that mean we have to register 'and' recode the car if we get the Deka battery?
You're correct on the OEM battery specs. Those aftermarket values may be close enough that you can escape coding (but not registration) if you truly feel the need to buy an aftermarket battery. I can't remember the exact details and I don't have them in front of me, but I believe there are only about 4 possible values for amp-hour coding, and I think those are 60, 70, 90, and 110. Of course not all cars should be run on all of those types of batteries; that's just what BMW's software that they use across their entire product line supports.