girlfriends 13 2.5 LS malibu was using about a qt in a thousand miles with a dexos spec 5-20 semi-syn oil, enter a 10 -30 fake synthetic group III + oil consumption almost totally ceased!!! no xxW20 oils anymore!!
I've owned mine since 15 miles, never consumed a drop of oil in 36k. I've aslo used full synthetic 0w20 since 4k.
How many miles on the car? I think the limit is 1 quart per 2,000 miles. May need to start a oil consumption test with the dealership.