Not sure which, either the rear axle carrier or trailing arm was extremely damaged to one side, so I decided why not change the whole thing. After one phone call this came, the old one out, and new one in, luckily it came with the bigger 535 output shaft so it was a plus to me. Things were really cheap then, I can't remember the exact price but I think it was about 7,000. This included the disc brakes, the whole trailing arm with 535 output shafts but not including the rear axle though.