Just got done with a HG. Now only after warmed up, idling in "Neutral" no brake or clutch, the truck has bad pulsing. The timing chain is lined up, the timing is set, the valves have been checked and tightened. Once it is put in gear and I let off the clutch, the vibration stops immediately regardless of speed. I can feel the vibration in the steering wheel as well as the dash. The vibration causes several rattles throughout the truck and is annoying as hell. Before I lift it and put 33s to hit some trails, I am trying to get the bugs worked out.

Thanks and Happy Easter

 

Bad harmonic balancer?

 

Someone has had to have seen or had this happen before. Very bad vibration in neutral, no clutch, no brake, as soon as gear is engaged the vibration immediately ceases. What changes with the engine when in gear?