Let me rephrase that, I knew when the truck motivation stopped and the motor was still running and the trans was spinning and after a shut off it would not re-start and the crank wasn't turning but the starter was, I felt sure the flywheel was broken or the flex plate was broken or the bolts had backed out. Prior to that I had no reason to think about the flywheel. Since I never removed anything myself I would not know the flywheel condition I would assume they checked it the two times they had the transmissions out.
