What's the difference between the transmission output shaft & the differential? on 1998 Audi A6 Quattro

I've been told my output shaft seal is leaking, also rear differential output shaft left and right are leaking & the Vanos valve both left & right are leaking. I'm told the Vanos valves are located below the valve cover gaskets & require removal of the valve covers for resealing. I've spent $1400 for water pump and was wondering if this should've been brought to my attention at that time?

by in Milwaukee, WI on September 08, 2011
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1 answer 2 comments
ANSWER by , September 08, 2011
your water pump is cooling system related. it has nothing to do with your other issues. did you request these be inspected?? what was your original problem when you went to the shop?? Roy
COMMENT by , September 08, 2011
The waterpump was the last work done on my car. I recently had it looked at due to off and on oil leaks beneath the car. I was also told the air filter & cabin filter are heavily soiled & the cowl area is very dirty.
COMMENT by , September 08, 2011
ok, so it was another visit for the oil leaks there is an output shaft seal on the transaxle. straight forward repair. the differential is another story. what did they tell you was wrong with the differential?? Roy