20w50
synthetic on break in? Fnd a mechanic wtf. Should have been 10w30 Dino. Don't give bs about corvettes comming from factory with
synthetic. Did GM hone your block with their $1mm machine? You probably glazed the cylinders. You should see cross hatching after 100k miles. The cross hatching is what holds the
oil, if you don't see it cylinders are glazed and need rehoned.