Noise in V6 100

[Ayrton Senna <qwe@wam.umd.edu>]

Last night as I was driving back home from a grueling study session I 
noticed there was a funny cranking grinding kind of noise emminating from 
under the chassis...aft of the engine. The engine itself still is smooth and 
seems to be perfect working order. The car still runs fine and shifts 
"very very smoothly" (Quote from a friend who drives a Lexus)
Can anyone help me on this before I take it to the dealer and shell out 
some more cash on this? Or atleast so I can brace myself for some shock...

Thank you