Clutch or Trans causing my speedometer fluctuate under full load?

Yes It shakes when parked, shakes with clutch depressed or engaged. Just seems to change a bit under different conditions. Shake does seem to continue when I push clutch and coast, untill speed drops a bit. I have even noticed the shake gets a bit more aggressive when I am slowing down using the jake brake.

 

Still looking for the cause of my frustration. I was told yesterday by a tech that I am experiencing "torque shudder". Does anyone have any experience with this, could this really be aggressive enough to make my speedometer jump around when shuddering. I have more hp and torque than factory, but I didn't think it was tuned to that much extreme. I still think I have a mechanical balance issue. I feel a shake at idle, and as I raise the throttle, things just seem to shake at different rpms. My mirrors shake at most all rpms and seem to be even worse in reverse, which I feel is odd.

 

Thanks for everyone's ideas! I did go back into the shop again, and as usual " They Know What i am feeling, but they just can't find it." They say " It must be due to the High Horsepower" Im not sold. My mirrors shake bad empty or loaded moving or not moving. I only drive 64 mph to try for best fuel mileage. The mirrors even shake when I am in reverse trying to back in. ( usually worse than in forward gears) Could my PTO box have something bent in it. The shop did say they sent it away to be rebuilt when my transmission was changed, but the PTO was not balanced. I don't know if a PTO box can be balanced. Is my "New" flywheel got something out of balance? Maybe my Moto Mirrors are just worn out. I don't think thats it either, because I can see the cab brackets shake also. Maybe I am just crazy, but I see, feel, and hear something!

 

No, PTO is only engaged when I am pumping off. I do not know the internals of an Eaton 18 speed transmission, but I had a guy in the past tell me there are still parts/shaft that is spinning inside the PTO box even when not engaged. I have no idea, and hope someone will set me strait on this issue, and then I could eliminate one part. No aftermarket cam or injectors. Just exhaust manifold and single turbo and a tune. I have thought about the ecm being an issue, maybe the tune didn't mix well with my original. I will try and locate a stock 625hp ecm and see if I can give it a try.

Thanks for Ideas

 

Well I am still at this crazy issue. Does anyone know if an out of balance clutch, or flywheel could make a cat engine run like it is out of timing. This thing feels that way, and is especially noticeable when in reverse. At this time the mirrors are shaking at their worst also. Or do I have an ECM tune problem?