Well I don't know how long it's been out there but I found out the hard way today. It happened on my 2003 SS on the way home. Guess the fluid had leaked into the oil and I barley made it home. Engine like came on so I call OnStar and diagnostic was, something wrong with the engine (DUH). Had it towed and they told me it was the engine needed to be replace as it's was probably a rod going through the block and damaging the crankshaft requiring and new engine. So a rebuilt engine has been found and it will be about a week before I get it back. Total estimate, $4500 +. Ugly

 

the head gaskets on the 3.5 do have a problem with the dex drool grud it eats threw them like a heart beat. i had head work done on my 07 already but it was do to a quiet recall on the head gasket water pump thing. the dealer tech and service writer looked at me and said what bill and i drove away