welcome to my world! i have the same symptoms and after saying only both cv shafts are grooved and need to be replaced they find out the diff is fed up and there is metal shavings in the fluid. bad news isnt it.
let me know what happens

tony

2004 silver srt-4 with some mods(FOR SALE) ;-) 1998 t-red CSVT stock and beat up :-( 1997 z24 cavalier with some mods(FOR SALE) :-? old ride- 98 Silver CSVT with some mods ;-)