Originally Posted by reevo
what battery you guys are using to replace 2008 e92.
I just (a few minutes ago) put an AutoZone H7-AGM in my 2008 E90. Don't know if your car is the same. The AutoZone H7 fit like a glove. I just had to reverse which end of the battery had the plug in the vent line hole. Thanks to GeneralXception for the excellent DIY.
The AutoZone website says H8 or group 49, but the one that came out of the car is a H7 form factor. I think the H8 might fit but it would be really tough to get it in there. Which battery you have might depend on how many extras are on your car (e.g. winter package). There are a series of holes in the floor of the battery box that allow other length batteries to be used, including one that probably would work for the longer H8. However, my car did not have the hold down with the long bolt on it as shown in the DIY, so I had to reach down in there to pull it out. That would have been tough to impossible to replace with an H8 battery.