You folks are lumping multiple problems together.
The 2.5L has the oil starvation problem.
Hence the right hand sweeper failures
, multiple revised oil pans, oil pickup, crank windage tray, oil dipstick, etc.
The 3L block has the suspected zircon problem from the 3L Duratec mold. (it's the mold not the actual process that is "suspect" )
Also it's only a casting range of an unknown time frame. It is not every single one that has the small chance for this contamination.
Brad's advice is likely the best insurance. Buy a block with some miles on it and do a full tear down and cleaning. It would be the best way to reduce the chance of being a "hit"
Personally I saw nothing in my block when I had it apart nor when I cleaned out the passages. I'd sure like to keep it that way.
