Greg571

Guys, thanks much for the input. Cracked flex plate is quite a bit cheaper than a crate motor. Going to have it checked by a pro on Wednesday. Got my fingers crossed. Not a job I can do.....Oil looks clean and pressure is good. I don’t have the inspection cover on the bell housing though. Thought about pulling the starter and plastic shield to take a look....

2001 Silverado 1500 HD with 6.0 liter motor. Has run strong for many years, and not treated like a work truck. Oil changed every 4K to 5k. Started up and my son head a bang noise and then the knock. Shut it off. I then started it, heard the knock. Pulled off plug wires one at a time and heard no change in the knock. Hoping it’s the flexplate and not a rod or spun bearing.......can anyone help or make a suggestion??