losing oil

every time i do a oil change i take out 2 liters of oil from my engine does anyone what could this be my car 2003 gmc envoy slt v8

Are you saying that a 5 qt oil pan only drains about 2 qts, if so when do you check the oil during normal use, it would show very low, no? You need a liter/qt/mile figure for any help here.