Theres oil in the radiator and the overflow tank of my 2002 GMC Envoy. The oil is fine, and has no water in it. The SUV gets regular oil changes, and the oil presure is fine. Water temperature is mostly normal, never overheating (not yet anyways).
What's got me stumped is that the oil is not low despite the amount in the coolant, and the oil does not have water or antifreeze in it.
Is this a blown head gasket? Or maybe someone at the oil change station had no clue what they were doing and put oil in the overflow tank? I noticed this oil about 6 days after changing the oil, when the sixth cylinder started to misfire.
I changed all the plugs and coils, but in the process found oil in the overflow tank. Engine is running fine and sounds normal at this point.