I just bought a 97 A6 Quattro, has 93k, when I make a left, or right, turn, I feel a minor rumble coming from the front wheel, or wheels. It is by no means dramatic, it is very mild, but I am not use to this after having driven rear drive wheel 2x cars.

Is this a normal thing, or is it an early indicator for front drive maintenance?

 

Quattro's always have a little rumble when turning, you may be leaking gear oil out of the propshaft seal at the rear of the tranny. Check to see if there is any fluid leaking where the propshaft connects to the transmission, if its leaking get the seal replaced and the torsen diff re-filled.
Also check the CV axles for torn boots.

 

Because all of the wheels on your car get power, when you make a turn the outside wheel has to travel farther than the inside wheel. The (slip diff or clutch packs) wheels power has to be absorbed somewhere because one power source can't drive two different distances at the same time. You way even hear a light click or noise from the front under hard slow speed turns.