BMW vehicles are designed with precise measurements. Therefore using a Quick-Lube Battery like Walmart or Costo will not work for your BMW. It requires a Genuine BMW Battery. Here's why. On the Battery itself is a sensor called the IBS. Intelligent battery sensor. It measures the state of health & state of charge of the battery in real time & reports that info to the engine control unit. Which intern evaluates that info & changes the alternator charge rate. It can increase the output up to 15.5 Volts. This is unique to BMW modern technologies & requests a BMW scanner to register. Your everyday Japanese vehicle only has a fixed alternator producing 13.8 volts. So you can see how important it is to install the CORRECT battery & register it to the computer so the entire electrical system operates efficiently, & trouble free. After the battery replacement depending on the model of car there are calibrations that may need to be performed to other sensors. This alone is one reason DIY on BMW vehicles is becoming harder & more challenging. Our techs take over 40 hours of training a year from industry leaders & manufactures so we can stay on top of this....so you don't have to.