Hope maybe someone could help me out.
Just did the spoa on my 90 sammy.
I already had 1.5" lift springs and 1" lift shackles.
The spoa was high perch.
I am guessing around 8" overall.

My questions are:

1. Was I supposed to change my u-joints? I get some vibes in first and second.

2. If my bad vibes continue, can I run a toy front shaft.
I have the larger Suzuki flanges.

3. Is it a direct bolt up or do I need one of those rat adapters?

Thanks for taking the time to post any info.

You didn't mention any driveline spacers? If you didn't use any your driveline is binding up that is why you are feeling vibration.

The pinion angle on the rear may be too much for the rear u-joints. Regular U-joints will take up to 3 degrees off the centerline before binding starts.  A Toy driveshaft along with raising the rear pinion angle until there is no angle on the u-joint when the vehicle is at rest will solve most binding problems.  The Double-cardan end of the shaft (which should be attached to the transfer case) takes care of the rest of the severe angles as the Double-Cardan joint can handle more extreme angles.

I would check at Rat's website (link somewhare here at Zukiworld) for sure, but I think adapters are necessary for all years of Samurai.

I have heard that Toyota axles can be hard on the transfer case's output bearing as the Double Cardan end of the shaft is pretty heavy...  I guess I'll know that pretty soon as I am installing a Toy front axle soon and will have a post the results at Ack's FAQ.

Also, did you align the driveshaft pieces by the marks on them?  Excessive binding WILL (not "can") occur if the u-joints are not aligned to each other!

Yes, I used a 1" spacer on the rear, and a 1/2" on the front.
We split the difference on the pinion angle.
What I mean is we set it between pointing directly at the t-case output shaft and where it was originaly.
This was so the pinion should be pointing almost directly at the output shaft under load.

Ack, good point on the wight of the cardan shaft.
Never thought about that.
Maybe I should wait and see how you make out, and  ask a few others that have done this mod. I found the rat adapter website. I don't think I could make them too much cheaper than that.

The u-joints don't feel like thier binding, but I am now hearing the "clunk" on acceleration as well as deceleration.
I think I will replace the u-joints and go from there.
If it still vibrates then maybe go an inch lower on the shackles.
I guess I can always shim if it is still too steep.

Thanks for the replies.

I would strongly suggest the Toy CV D-shaft.  Yea, it weighs a little more, but I've had mine for over two years with no problems.  I have a pretty tall lift on mine and it solved a lot of the problems I was having.

 

I changed the u-joints in the rear d-shaft.
It helped some, but I definately have some vibration still.

It also sounds like the front d-shaft is rubbing the crossmember on deceleration.

Has anyone heard of these problems?
What was done to correct them if so.

You may also want to look into putting a traction bar (aka - anti-wrap kit) in the rear.  I did a spoa with shorter pads and had alot of clucks and rattles from the axle wrapping under acceleration and braking.  I bet taller spring pads would only be worse. 

That makes sense.
I have one ready to go in, just have to weld the rear mount.
Maybe I should do that first before changing sackles, etc.?

Also, we set the pinion angle up towards the t-case output shaft.
I am still runnung a samurai d-shaft.
Could this be my problem?

That could be one of them, the stock drive shaft likes to have both flanges parallel(sp) the toyota drive line would be good but there are two diffrent ones that I know of, one is no better than the stock sammie one that you have now, hardly any flex to it at all, I think the one you want is the earlyer one,I would still get rid of the shackles to get it closer to 6.5 inches of lift and get rid of the drive line spacers and go with an extended yoke and grind the ends of the drive shafts a little the part that holds the u-joints in that would hit each other while flexed all the way, have fun.

Your right.
I have a bit too much lift.
I think it looks nice, but it wouldn't look bad down an inch either.

I'll see if that cures some of my rattlin' blues.   

don't know if any one else said this .. but have you tried shimming the diff, to bring the angle back up to a more tolerable area for the u joints,, did that on my buddies 85 seemed  to fix the prob no more vibes...

Thanks for that suggestion as well.
I am going to return to stock or near stock shackles. 3 and 5/8" is stock???
8" total lift is prolly a little much for 31's anyhow.
This should reduce the driveline angle a bit right?
If it still vibrates alot, then shims would be the best option other than a toy shaft or pulling it back out to reset the perches. 

Thanks to everyone for the suggestions.