not sure as we went to a friend's yard and spent 6 hours measuring and found 4 of them,, then we had to machine off the flange where the ring gear bolts on, and on another one we had to add a spacer to the ring gear to get the ring and pinon to line up,, then we found a couple of set of gears that bolt on, no mods,, so to answer your question, the one thing i do know is it came from a Mercedes. yes we are using a crossfire diff housing. when all is done i will post all the part numbers and how we did it.. we are also looking at the ford 9". and making that a bolt in,,, that is all i can say about the Ford 9" at this time. jim