I've been experiencing a strong clunking sound (can even feel it) from the rear differential / axle area. The noise relates with vehicle speed. There is also a leak from around one side of the differential and damage to the ring gear.

I'm really having trouble identifying the culprit. Any ideas?

 

sounds like your carrier has dropped its clips out. you need to get it fixed before it wrecks your entire axle. i just had to do mine. what happens is the clips holding the friction plates fall out and get chewed up in your ring and pinion. when you opened the diff cover did you notice metal chunks along with a lot of shavings on the magnet? if it is the carrier you can get a rebuild kit for it to replace the clips but i decided to replace it entirely so i wouldnt have to worry about it ever again. got the Eaton limited slip Truetrac. its amazing. i would do that carrier, new ring and pinion, and new bearings. old ones will have metal shavings in them for sure and fail.