Ford Repair: rear end, rear end, time what kind

Question
my rear end is roaring. Can I fix it without having to change the entire rear end

Answer
well of course you can , if you give me more info , like when it is making noise., or is it when you give it gas and let go and noise is gone or is the noise all the time , what kind of ford it could just be bearings, more info and i will try to help as much as i can