My build is just about complete, but after putting in new springs and an SPOA kit. I'm getting crazy strong vibrations and shaking when accelerating at any speed. Feels like the whole thing is going to fall apart it shakes so violently.

the front drive shaft rubbed slightly on the cross member, so I took the drive shaft out completely, and its still there. I'm reading now about u-joint alignment, angles, etc...
I'm wondering if being at such a steep angle after the lift if causing the problem? I installed a spacer, and while doing the build I didn't read about any issues like this. Hopefully someone has some insight. I have not installed lower gears or any reinforcement on the transfer case.

Here are a couple pics

Assuming you didn't move the vehicle between those 2 pics, your driveshaft is out of phase. The yokes should be at the same angle front & rear like this: >-------<  (hope that makes sense?) Remove the front yoke from the xfer case, & slide the slip-joint apart & reassemble so the 'C's are parallel. I think there may be a dimple on each section to line it up properly.

Hth,
Fuzz

oh ok. I see what you mean. I will line those up and see what happens. thank you!

I saw that and thought the same thing

well I lined em up   }-------{   and it worked great! what a relief! i thought I made some huge mistake during the build.

about 80% of the shaking and vibration is gone. Driving it is bearable now. It still has a little ways to go before it feels solid, which I imagine is somewhat normal.
Any tips or advice to get it tightened up and reduce the vibrations?

Post another pic, we want to check your work, get both ends in 1 shot and then of both ends

Wild

Looks good, the only other thing you might try is rotating the yoke
180* to see if the vibration is reduced or gone.

The 2 parts are phased correctly right now, but they may have been
balanced from the factory 180* from the currently assembled position.

The front shaft on my Kick had a high speed vibration from being put
back on the diff flange in a different position, I had to index it twice
to get it to go away.

Good Job

Wild

i'll give that a try. thank you

You may wan to think about a longer slip yoke, to my eye it looks like you only have an inch or two of over lap. just a suggestion

is that spacer the  1"? It still looks like the shaft is a little short and this will cause some vibes. Make sure to shoot some grease into the slip yoke and it might get rid of some looseness. Is there any movement in the ujoints? any little bit of looseness will cause issues.

Another thing I didn't see anyone touch upon was that with u-joint style drivelines the flanges need to be parallel to each other. I think you have some angle shims in your spring perch to angle the pinion up. While this helps with bind, it's wrong for vibes and u-joint life.  On timing the drive line there is a good picture of the factory marks that you'll want to line up. It's in our archives, let me dig up the link.....

Ok, here it is...
From the article here: http://www.zukiworld.com/month_050104/feature_trailtough_yjlift_install.htm





You've got a lot of lift there with the SPOA and lift springs so it's going to be hard to get a vibe-free ride and your u-joint life is going to be shortened quite a bit too.. Sorry.

Hope that helps.

-Eric

I had the same problem it was a shimming issue I called Brent he told me to park on something level take off drive shaft buy a cheap degree finder from home depot and hold it on your pinion and see what the degres was I forgot what it needs to be you can call him and see or someone on here can tell you.But mine needed 3 degres shims put them on solved all my problems I would get still shims I got pot metal was no good they didn't last very long

thanks for all the input!

I lined up the flanges with the small marks. Still have the shaking still. I did notice a little play in the shaft. I'm attaching a video to show what I see, and what I hear when driving.

I do not have any shims, and didn't really do anything regarding the pinion when doing the build. Now I'm starting to wonder if the spring perches aren't perfectly level or something? Maybe thats another factor?

I also looked at the slip yoke (possibly needing a longer one) and it did feel tighter with less play when I slid it up further. Would it do any good to put another spacer on the other end (I have an extra one). Or maybe just order the 2" slip yoke and get rid of the spacer I have now. Or maybe a CV type driveline?

Thanks again for all the input. its my first build and obviously learning by trial and error.

Here is the video

Samurai Vibrations

I think you have several problems, the pinion shaft looks like it's loose, the U-joints look loose, and the
splines are probably hanging out too far, which will cause the whole shaft to oscillate, furthering the
vibrations you are getting.

I don't see a problem with using the other spacer on the trans, but someone else might
chime in and tell you if it's a bad idea

Wild