Curious, since I just bought a 6.5L 3500 of the 96 model year and harmonic balancers seem to kill these engines. How does one tell if the harmonic balancer is bad without having to take stuff apart? Am providing a video of the engine running during shutdown, as I read somewhere that a "thump" at shutdown is one main symptom of a bad balancer. Don't know what that "thump" is referring too, and whether or not my engine does it. Much thanks. Truck has 220,000 miles on it. The buzzing in the video was just my phone vibrating with the truck, sorry.