Subaru Repair: front end differential, thump thump thump, subaru forester

Question
I have a 99 Subaru Forester with 95,000 miles on it.  Last week, I had both front axles replaced.  Now the car is making a thump-thump-thump sound whenever I make a tight turn at slow speeds (i.e. parallel parking).  The dealer thinks it's the front end differential.  Now the tricky part.  It wasn't doing this before I went in and apparently there was a bearing on the left front axle that took them hours and a slide hammer to get off and replace.
My question(s):  do you think that it is the front end differential and if so, do you think all that slide hammering could have broken it?  Also, do have an idea as to the repair costs for a front end differential?.

Answer
Sometimes the front axle wont push out of the front wheel bearing without difficulty.And is very frustrating.Its possible the front wheel bearing was damaged in this process.I would go talk to the shop about it and see what you can work out.But i am confused about the slide hammer part that's not the correct process.

Justin
All Wheel Drive Auto