Another vibration thread.
At 70 mph foot off the gas nothing, Alittle gas and it starts to come on. OD on or off.. not real bad but anoying. I started another thread about the exhaust damper,, maybe cause its hitting my oil pan???? The clamp part is

 

Check out my newly posted thread - "Superduty Drive-Line and Rear-End Vibrations"

 

I took off that damper on the exhaust which was hitting my oil pan and the noise is gone. Thanks