hi, my FRS has had the ford sub woofer fitted to it. you need the ford 9009 subwoofer and the ford 9009 head unit as the st 6006 doesnt have aux in to run the amp. im not sure what the amp is with the audio package, mine is jbl but i don't know if that's what ford packaged it with. there may be more you need, i'm not sure, HTH.