[ngoma]

Very good, very methodical, very detailed explanation.

Yes so maybe we can find out more about what went into this HG R/R.

What was the surface preparation? Was it sufficient for the HG type (fiber or MLS)? Some experienced D24T-ers swear by a very light misting of Hylomar spray dusting on both sides of the HG.

Was the cylinder head checked for excessive warping or twist?

What type of fasteners? Original type triple-square screws, or studs? New or reused?

How tightened? In stages? What torque levels? Beam or clicker wrench? (as v8volvo mentioned above).

Re-torqued after 1,000 miles?



Also-- We should not categorically rule out the possibility of a defective oil cooler, even a new one. Although the symptoms do appear to be more consistent with HG failure, as stated above.