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cv shaft and shackle flip, still vibrates. [Final say]

That is proper.

I had read some where they need to be phased 90* from each other. Then I started looking and noticed mine are all the same direction. The rear is just SLIGHTLY off of perfectly lined up with the CV side.
 
They should be set up how yours is. Like this one.

208-1350cv1.jpg
 
Ok guys, I took a few more pics. I also talked to Kurt. He is wondering if it could be any other issues.

I am out of ideas to check. The CV portion doesn't bind when I spin the shaft by hand. The pinion measures out to between .5* and 0*. According to H.A.D's site the pinion can be angled up to 0*. It has to be something drive shaft / angle related because it doesn't vibrate as bad under heavy acceleration. Once I let up and cruise it starts.

My bushings in the rear springs are dry rotted and not pretty but neither Kurt or I feel like that could really be the issue.

Blumenthal's in OKC has reluctantly offered to re-balance the shaft. With the way the vibration reacts to speed and load it seems like the shaft balance is not really the issues though. It just seems insane to me that only a 4 inch lift would be giving me all these problems.

The part #'s for all the things they replaced are: (as quoted by phone)

Neapco -

N3-281747-1x
N2-86-418

Spicer u joints-

5-795x
404-0a
5-1350-x

Side view 1.JPG

Side view, pinion close.JPG

Side view 2.JPG

Pinion angle.JPG

Drive shaft Pinion side.JPG
 
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The pinion nut could be loose or pinion bearing bad. You haven't had the yoke off, have you? What was the last setup where it ran without vibrations?
 
The pinion nut could be loose or pinion bearing bad. You haven't had the yoke off, have you? What was the last setup where it ran without vibrations?

Yoke has not been off. No vibrations pre lift and pre cv shaft.
 
Tailshaft bushing on the transfer case...... It would react differently under load and coasting. and would be amplified by the lift and change in position of the slip yoke from the original.

Cheap fix since you have tried everything else.
 
Man, my setup is identical to yours except I have 6" shackles.

My rear shaft couldn't even be balanced by the guy that cut it down. But I went 70+ on the way to the dunes and have zero vibration...

image.jpg
 
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Man, my setup is identical to yours except I have 6" shackles.

My rear shaft couldn't even be balanced by the guy that cut it down. But I went 70+ on the way to the dunes and have zero vibration...

:dunno: could you maybe measure your angles and post them up? I'm pretty much grasping at straws at this point.

Edit: just noticed the angles are on your drawing. Just saw the 33" the first time. Are they the current angles or was that your pre-shaft measuring?
 
I'm going to have to bet a u joint installed funky, or the tail shaft bushing.

Well if the shop installed the ujoints then balanced it, that should eliminate ujoints as an issue? Or do they only flat balance it?

How would the tail shaft bushing cause vibration, does it not just seal the fluid in? I will replace it, just trying to understand all of its functions.
 
The bushing is there to stabilize the slip yoke, it doesn't seal fluid.
 
So driveshaft is fixed and profesionally balanced.

Check tires for balance, check wheel bearings. Check pinion bearings. I have learned just cause it didn't have it before doesn't mean something really weird didn't happen
 
On the tail shaft, there is the seal, but behind the seal, there is a brass bushing that supportstthe yolk.
 
So driveshaft is fixed and profesionally balanced.

Check tires for balance, check wheel bearings. Check pinion bearings. I have learned just cause it didn't have it before doesn't mean something really weird didn't happen

It certainly doesn't feel like a tire vibration. I guess I can take it up to discount and have them balance the tires.

Bearings are good. I was planing on spinning the pinion and feeling it when I got off work tonight.

Is the bushing replaceable with just pulling off the seal or do I need to bring the whole housing down to get it pressed in?
 
It certainly doesn't feel like a tire vibration. I guess I can take it up to discount and have them balance the tires.

Bearings are good. I was planing on spinning the pinion and feeling it when I got off work tonight.

Is the bushing replaceable with just pulling off the seal or do I need to bring the whole housing down to get it pressed in?

When checking the pinion bearings be sure there's no load on the driveshaft. Chock the wheels and take it out of gear then push/pull/poke & prod for up/down/in/out/side to side play of the yoke.

You will need to pull the tail cone to replace the bushing. Be careful when installing the new bushing as it's soft bronze and can get damaged easily. Maybe borrow or rent a race / seal driver kit.
 
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