Hello all Hopefully someone has experience with this. A few years back I bought a 2001 CHevy 2500 HD 6.0. This truck has been used hard, it was a snow truck at a DC the size of a city block in Michigan. Since the day I bought it, there has been an engine tick. The only time you can hear it is when you drive over 50 miles per hour for more then 30 seconds, like cruise on the highway. If you get off the highway an drive it under 50 the tick goes away. Other than that, the engine runs fine (and it has a very healthy appetite for gas, I rarely drive it). Anyone care to guess what that tick is? I took it to a dealer and was told they would have to tear into the engine to find out what that is, which is at least $400.00 right there without fixing a thing.