There are a lot of misconceptions regarding the parts that go into BMWs during Service and production, especially when it comes to OEM Parts vs. Aftermarket Parts. As a consumer, I feel it is pretty important to know what these terms actually mean, and how they affect the longevity of your BMW. I field an amazing amount of calls by potential customers concerned with OEM parts going into their BMW, all the while many do not understand what OEM actually defines when it comes to the description of a particular BMW part. So . . . let us expose a few terms, what they actually mean, and how they affect your BMW.