This problem developed well before the end of the warranty and GM did a modification by replacing all the piton rings. Still had this major problem 1qt+ every 1000miles which GM said it is acceptable Now at 75000 miles have developed an engine problem and the dealer says I have to have a new engine as the cyl is warped . A problem that from the beginning was the cause of my engine oil. Unbelievable, really believe in buying our US products, even though the rest of the family have foreign makes that some how do not seem to have the same problems.