I bought this car new from a central Texas GM dealer. It has presented me with little to no problems during my ownership save a total failure of the unit that houses the speedo/Tac and all warning lights and indicators (replaced under warranty), and the failure of the AC approximately 7 years ago (which I totally replaced myself - and it hasn't missed a beat since), and I have also replaced the "knock sensors," Brakes x 2, "leather" on the front seats and "rear lift gate shocks" once. It has also suffered a couple accidents and two incidents of hail damage, all totally and professionally repaired to like "new" condition. It has approximately 280000 miles on it. Everything works well and it drives like a new car. Here's the problem; I've religiously changed the oil (Castrol) every 3000 miles since new. But, over the last 10000 miles, I've noticed that the car is using an excessive amount of oil. I have absolutely no oil spots on the driveway/garage floor and never have, and the underside of the car is completely dry. I recently drove it 100+ miles with my wife in close trail and then I followed her while she drove it and there was absolutely no smoke at all whether at high or low speed (we have an 85MPH toll road 5 miles from the house). After reading numerous (over 100) on-line comments about other 2003 to 2009 Chevy owners experiencing the same oil loss "Phenomenon," I suspect my adherence to a 3000 mile mandatory oil change may have covered up a "long time" oil loss that I just didn't pay attention to. I suspect this is a bigger deal than my simple and recent discovery. There is something "amiss" in this GM engine. I'd like to know what it is and can it be fixed before my wife makes me donate it.