Its really annoying. To the point where I just shut high idle off. When high idle engages and the RPMs climb, the truck shakes back and forth like its running on 5 cylinders. I opened the hood and the engine was dancing side to side moving about an inch in either direction. It does it (the shakiing thing) also if I take control of RPM manually with the Tech 2. Anything over ~1050 RPM and the engine starts to shake. Whats wierd is it does not shake half as badly if I raise the RPM by engaging the PTO feature (wiuth the cruise control). It does not shake AT ALL If i just hold it at 1200 rpm or so with the accellerator pedal. The only thing I can think of is im running a PPE HOT Xcellerator, and that amybe the tune is so touchy that the ECM is constantly bouncing off the rev limiter and cant hold the RPM constant. Also, it only seems to shake after the engine is above 160 degrees or so ECT. ARRRGHH!

--Ben

this seems similar to what you are experiencing. I'm sure the specifics are different though

http://www.dieselplace.com/forum/showthread.php?t=61867

mine does NOT shake at all in park, idle, and it does NOT shake when you slowly increase revs with the pedal. It ONLY shakes when high idle engages, or when you command a high idle with the Tech2.

I hope its not something with my torque converter. I thought I was done with that!