LS1 Head Gasket.
Thanks!!
The ONLY place that can happen, is the block; or, if your car has the oil -> water "cooler" in the radiator, there.
I STONGLY suggest that before spending A DIME on any parts to "repair" this, that you find out EXACTLY where the mixing is occurring. Your current diagnosis is incorrect and anything you do is not likely to resolve it.
Whatever "explanation" you / we come up with here, it HAS TO account for ALL the facts we see. If a proposed "explanation" DOESN'T account for ALL the facts, then a new explanation is called for. Don't get all hung up on blaming something for your problem until you are sure that it's the ONLY explanation that fits ALL the facts.
(or at the very least, the by far most likely one)Keep in mind also, the trans fluid cooler can do something similar; but it can be a whole lot harder to spot coolant in the trans fluid. Assuming of course that you have an auto trans.






will post back once I find out what it actually is!