The100,000 mile 5 year WARRANTY expired less than two months previous to problem. Issue: Corrosion/ a hole occurred on internal water jacket between the # 2 & # 3 cylinders. The aluminum engine block had a hole in it allowing the engine oil to leak into the cooling system creating a problem that would be catastrophic to the engine if it was left unattended to. GM paid for about 1/3 of this 7,500 repair bill. I paid $2,200 out of pocket. They said it was a "one in a million" (paraphrased) problem but they knew exactly what was wrong with it about a half an hour after it was pulled into the shop. They did not take the engine apart to determine this. I complained to GM after the work was completed (and paid for) as I did not think that a vehicle with 89,000 miles on it should have this issue. The dealer would not release the vehicle from the shop before I paid for it. The dealer decided that they would not help me any further with the expense. I had to contact GM to find out their response. The dealer did not contact me about my request for further assistance. I was disappointed but I did not try any other possible remedies. I was wondering if there are other issues like this one.