2000 Cadillac Seville review from North America

I absolutely love my 2000 Cadillac Seville. She has more than adequate horsepower, traction braking and automatic windshield rain adjustment. With heated leather seats and seat adjustment combined with side mirror automatic change combined with two separate radio stations (five channels each person), this is truly the good life. However, my Caddy is loosing oil, not burning, but leaking. I lost five quarts and have been adding about on quart weekly. She is scheduled to be returned to the garage for another look very soon. Does anyone have any ideas as to the problem? Thank you, Pauli.