I installed a hack n tap and its a little worse then before 0-50 it's fine the after 50+ it's vibes

 

Pull your front shaft and drive it. Mine has vibes only when the front shaft is in. I replaced it with a new "woody" shaft and still have the same problem. Not sure what the cure is going to be.

 

How much lift?

Did you shim it properly to get the proper pinion angles?

 

^^^this

 

It's the rear shaft vibrating, would it do this if my output shaft isn't cut the the proper length.

 

Are you sure your tires are balanced? Have you thought about balancing your d-shaft? Is it an oem front shaft or aftermarket?

 

OEM shaft and I'm in the need of some new tires but its coming from the shaft

 

take a picture of your pinion angle

 

 

Yes.
The whole idea of doing and SYE is to shorten the length of the output shaft. The longer the shaft extending from the t-case, the more leverage it has to bind things up inside the case.
The length of the shaft and it's leverage have much to do with the vib's.

Consider this, the earlier Jeeps (pre '96 I believe) have a shorter output shaft than the post '96's... and, low and behold the pre '96's can typically be lifted to 4" without vib's, where as the longer shafted post '96's are know to vib at as littel as 1" (plenty of factory upcountries came off the lot with vibrations).

Cut the shaft to the lenght identified in your instructions.

 

Make sure every part of the shaft is greased. I had a shop install a brand new shaft with no grease.

 

are your leaf spring u-bolts really tight, check

 

No more vibes I checked my U Joints and one was shot. I went and pick up a precision U joint and works great. Yes everything on my jeep is tight.

 

Which u-joint was bad?

 

this first U joint in the double Carden it was shut all the little needle bearings where crushed and spun all to the bottom