2013 Peterbilt 386, 72" sleeper Shaking cab

Hello everyone. I'm looking for some advice or previous similarity issues someone here may have dealt with. I'm pulling an end dump trailer with my 2013 Peterbilt 386, 72" sleeper.

I have replaced kingpins, tires with rims, alignment, leaf spring bushings on my steering, carrier bearing, and most recently 3 of the U joints the driveline has between tranny and differential without any success of getting rid of my shaking. Steering wheel is perfectly fine, no shaking whatsoever, the shaking moves my cab and it's more like a bumpy shaking side to side, like if I had a bumpy tire. Any suggestions is highly appreciated

 

Other possible sources: harmonic balancer, engine and transmission mounts, nuts on the driveline yokes not tight. Also take a look at the cab: mounts, shocks and air bags.

 

Did you have the tires balanced ? I found/had an out of round steer tire which would cause a shake at higher speeds.

 

As mentioned, tires need to be spun balanced. They may be balanced, but once installed not perfectly mounted centered on a hub and now rolling out of round to cause issues like this.

 

Roughly 8 months ago my mechanic did a front seal replacement on this ISX-15 so I think he replaced the engine mounts as well while he was there

 

I bought tires and wheels as a deal from a private party almost new and steering tires had this self balance round weights inside, I could feel it when I load them on the back of my pick up

 

I also forgot to mention I replaced my brake drums to eliminate the possibility of a small amount of play on the studs

 

Even with no shaking in the steering wheel? OP stated the steering wheel is perfectly fine, no shaking whatsoever.

 

That is correct, my steering is fine but my steering tires will worn uneven too soon.

 

Noob question, I once heard that my yokes must be all line up in like same position which they are except my inter. Should that must be line up as well?