We’ve seen this far too many times to not address it, so here is a little helpful information about batteries and the virtues of having them installed correctly. When we are asked, “Why is the correct battery in my BMW so important? Aren’t all batteries just batteries?”
Pictured (right) is a 2003 BMW 530i. Someone thought they would save the owner some money and install a battery that was not meant for this application. In most vehicles this wouldn’t cause much harm, but in a BMW you can clearly see the results of battery acid vapors eroding the battery tray and paint around the battery’s location.
What’s not as readily apparent is the damage to the wiring and trunk lining material, as well as the potential health risks to the drivers and passengers over the course of a few years.
In the next photo (below) you can clearly see the vent hose hanging down between the fender well and the battery.
When the proper battery is installed the vent hose is connected to the battery and all acid vapor is directed out of the vehicle and out of harm’s way. BMW places batteries in the trunk for many good reasons:
1. To have the Ultimate Driving Machine the vehicle needs to be balanced. By placing the heavy battery in 
the trunk, weight is removed from the front of the car and helps to improve its handling characteristics.
2. Batteries last longer when kept out of the heat and vibrations of the engine bay. We have seen original batteries last as long as 8 years in a BMW.
3. Placing the battery in the trunk allows the safety disconnect to be placed at the battery which can help prevent a fire in the event of an accident.
We found these problems while performing unrelated repairs on the BMW pictured. This is just another example of why its important to take your BMW to a specialist like Coast Motor Werk. We thoroughly inspect all our cars for any problems or potential problems related to their BMW and provide honest feedback and fast repairs at reasonable prices.
