* Connecting Rod Failure: A connecting rod could have broken, allowing the piston to impact the cylinder wall or crankshaft. This is a very common cause of catastrophic engine failure in diesel engines.
* Crankshaft Failure: The crankshaft itself could have fractured, either due to fatigue or a manufacturing defect. This would prevent rotation.
* Piston Seizure: While you mention normal oil pressure, a localized lubrication failure within a cylinder could lead to piston seizure. This often causes a sudden and complete engine stop.
* Severe internal damage from a foreign object: While less likely, something significant, like a broken valve or a piece of a broken connecting rod, may have gotten into the crankcase and caused extensive damage.
Why it's hard to pinpoint without inspection:
The symptoms you describe are consistent with several serious mechanical failures. Determining the precise cause requires a physical inspection of the engine. You'll need to disassemble it to find the source of the problem. This is a job best left to qualified mechanics with experience working on diesel engines, especially Power Strokes which can be complex.
Do NOT attempt to restart the engine. Doing so could cause further and potentially irreparable damage.
You should have a qualified diesel mechanic diagnose and repair the issue. Trying to diagnose this remotely is impossible and could lead to further damage and potentially dangerous situations.
