Driveshaft too long? Tough installation and Vibes.

Let's start with this, I'm kinda new.

5" lift with RE leafs, Hack and Snatch SYE, Front drive shaft installed onto rear, 8.25 rear with new 4:56 and limited slip. 4 degree shims added.(started with 2 degree, no change in vibes)

Should I need to pry/beat the driveshaft to get it into the differential yoke? I had to pull the caps off the uv joint to install it.

When the driveshaft is in, there is no visible slip/space on the driveshaft slider. Front driveshaft has 1" slip/space between the ds parts.

Driveline vibes after 55.

Jeep did great on its first trip in the desert. Mostly sand. ( I towed it out there)


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You want the pinion yoke pointing at the transfer case yoke. It should have close to the same angle as the driveshaft. Same thing for the front DS. It could be casuing vibs as well.

Angles are good to go. My main question is the driveshaft too long? I have to pry it into the yoke, and there is no slip in the driveshaft . No vibes from the front end.

yes, sounds too long. perhaps a front shaft from a manual trans would work better in the rear. or get yours shortened.
not sure if it's causing your vibes, but it could cause binding and damage.

I was thinking, Maybe I can shorten up the transfer case output shaft, and the hack n snatch sye about an inch. Free modification before driveshaft reworking.

Your slip should have between 1 1/2" to 2" showing ... This puts the slip yoke in the optimal position. With no slip showing you risk serious damage ... either to the tcase itself or if you are lucky just the dust cap will suffer.
When installing the shaft, it should go in easily when collapsed and should need to stretched out to fit.

How do you know your angle is good if you said you started with 2 degree shim then went to 4 degrees shim? Have you actually checked it?

I agree sounds like the shaft is too long but it might not be causing the vibs.

I had the much the same situation...5.5" lift, using a stock auto XJ front DS on the rear with a Ford 8.8, 6* shims, and an H & T SYE and got driveline vibes about 60 mph. My rear DS was a full compression to the point that I had to jack up the Jeep from the crossmember to get enough slack to drop the shaft.

I paid $65 to have my drive shaft shortened by 1 1/2 inches and then rebalanced. Best $65 I could have spent. The vibes are still there, but much less noticable.

Im running a 6.5 lift with 4deg. shims and my angle is dead on. I have no vibration and I have about 1 1/4 of slip in my drive line ( with a 231 SYE ) I took a front DS and it modified to fit the rear.

DS is too long, what could have possibly happened is with the increase of lift, the tear axle 'moved forward' and therefore the shaft is not the proper length anymore. Easiest thing to do is find a shorter shaft or have yours cut down (pretty cheap to do) and balanced.