peterbilt shake/vibration

I've look through just about every post on here and am still stumped...
My truck shakes. And i mean it shakes to the point you cant see if a swift driver or a #### boeing 747 is next to you. The shake is the same throughtout the cab. The seat shakes, the steering wheel shakes, the hood shakes, the shifter shakes, the rearmost of the cab shakes. The entire trucks got the same shake all throughout it.
The shake can be felt around 40mph but starts around 50mph and peaks at about 58-59 and isnt quite as bad after 65mph. But i can still feel it before 50 and 65.
The shake started back in 03/19 after dropping my bags to get underneath a 13.5 underpass. However could have also been chicagos beautiful roads they have in the inner city area.

its a 2005 387 with a deleted single turbo c15, 13 speed , 3.35 gears
The engine was rebuilt 200k miles ago
Trans was replaced new 235k miles ago
the differentials were replaced 100k miles ago
drive shafts and u joints redone 50k miles ago
steers replaced with michelins 25k miles ago(tried other steers to no avail)
the tires were balanced 10k miles ago(drive)
all 10 aluminum rims were replaced 500 miles ago and all 10 wheels rebalanced
the drive shafts were re-balanced 100 miles ago

Ive checked and had a old timer mechanic rechecked every yoke on the driveshaft and the the entire front end over and over again. Honestly everything driveline related has been checked and/or replaced in the last 150k miles on a 1.2m miles truck.

 

Shaking is usually alignment

 

alignment was checked 3 weeks ago and was in below/better than spec.

kingpins and tire rods were replaced 6 months ago along with an alignment

alignment issues usually cause a pull and not a shake

however i did have a shake while braking that the kingpin/tie rod alignment fixed

 

Have you replaced the front tires!

 

replaced with brand new: no change. i did grab a set of mounted on rim similar Michelins from a O/O friend and there was no change

 

Only other thing I can think of is one time when one of my clutch plates came apart in the center the clutch still worked fine but the vibration was coming from the bad plate !!

 

hmmm.. ive been having clutch issues. grabs all of a sudden even if you try to release the clutch as slow as possible the cord has been replaced in the last two years and the clutch adjusted 3 times if i remember correctly

 

Have you changed brake drums in the meantime? Unbalanced drums will throw wheels out of balance.

 

Starting after the airbags got dropped... indicates that you bent a drive shaft.

the slip yoke took up all of the slack... And any movement beyond that caused damage.


Get runout checked on all shafts ASAP.