Remove the cover and drain. Use some ragss to wipe everything out and do a good inspection of the ring gear, spider gears and LSD is you have it. If nothing looks abnormal clean the mating surfaces of the cover and diff, use quality RTV and seal it up.
Some say to wait for the RTV to set-up. I just use the black RTV that is made for oil exposure and seal and fill. No waiting. Remeber to add the appropriate friction modifier if you have the LSD.
Just Got it, Give me time!