rear diff noise on my a4 quattro , info wanted please

[jamesey]

hi when i bought my quatt it made a slight noise when on full lock to the right when pulling out of a junction it was like crabbing i put that down to the 4wd of the car , ive got a jimny that does that in 4wd.
but now the temp had dropped when accelerating i can hear clunking from the rear of the car like its grinding , it only does it whilst under load , its a 2002 a4 quattro with 163k on the clock , what oil would this take and how much is in there , this is my weekend job (start with the cheapest option) is it lsd oil? ive no idea , .
ive had a look underneath the car and i can see the diff , it looks like there 2 drain plugs at the bottom /underneath the diff?
any help would be great as the winter is here and dont want to be stuck in 2wd lol

 

[moggs]

cant advise on oil but it has been covered before. Mine grinds but doesn't clunk so will be interested to see if the oil change helps, let us know.

 

[spartacus 68]

If you're doing this yourself you'll need a pump to put gear oil in, plus axle stands, chock front wheels, etc. Always release filler plug before pulling the drain plug. Run car to operating temperature to increase viscosity of oil. More details here: B6 A4: How to change your rear diff oil

B5 version (better pictures): AudiWorld Tech Articles