I was doing some maintenance on my mother's '99 Audi A6 and needed to consult the owner's manual. In so doing I came across a section that said the airbag should be replaced, even if never having been deployed, by the 14-year mark (why not 15?). I've come across one other reference like this, for Mercedes, but as the E36 model is getting pretty well up there in age, does anyone know anything further about this as it applies to BMWs, or other cars?