Thanks guys.
I believe it is a standard corolla diff but not really sure as they came with the car and the previous owner never had to change them so doesn't know either. Is there an easy way to check if they are corolla or celica diffs?
I had heard about putting complete hilux or similar diffs into corolla's but i believe that requires quite a bit of work to mount it and make it fit (which would be out of my mechanical ability.)