Has anyone else had problems with the "stabilitrack" system on an '08 Envoy. They had a recall on it - I took it in for the recall. They did "whatever" and it's been back 4 more times. The light comes on anyway the system is pressed into operation. And stays on!!!! I take it in - the shop checks it out and changes some parts here and there and proclaims it "fixed!!!" until 24 hrs later when the light is back on!!! Anyone else???