So I recently got my Jeep the 3.5" Rubicon lift,

http://i116.photobucket.com/albums/o24/Kotrin/Jeep%2098/P1000180.jpg

I know the tires look out of place, but that will come in time. Well I noticed that my driveline around 30 mph shakes, but it goes away. I talked to the shop that did the work and it does occasionally happen. They suggested I do a slip yoke eliminator and a new drive line which would fix this, or lower my transfer case (I would rather not having things lower to the ground IMO). I guess my question is will this fix my issue, 2 is it okay to still drive it (dont have the cash atm to just fix it). Am I still going to have the flex and everything that should be correct? I guess I dont fully understand what the slip yoke eliminator is suppose to do. I know it gives your driveline a proper angle, just it seem's to cost around 600 buck's or so for the parts to get it done(including new driveline). Any help would be apperciated.

when you got the lift did you get a longer drive line to go with the lift? the stock DL is to short for max flex and can cause your u-joints to bind or blow.
you can get a longer DL for about $150 with your DL as a core. it will help but you may get some vibes around 75mph. and you can do all the flexing you want. if you get a 4in. lift then it is a must to get the sye. an sye is a fixed yoke (that means that the DL doesnot slide in and out of the transfer case) where the DL is a direct bolt-on to the transfer case and its the DL that slides in and out in its self. one of the great thing about the sye is that if you bust a u-joint you can replace it with-out making a mess. as with your slip yoke when you pull your DL out of the transfer case you will have lots of trany fluid pouring out.

It sounds like the driveline angle is now off from the lift, this as stated above is causing the vibrations.

I would suggest looking into the SYE kit and look into getting a CV drive shaft.

then make sure the rear axle pinion is in the correct position. If you run without a CV shaft then the pinion angle and the angle of the output shaft of the x-fer case must be the same.

If you run the CV shaft then you want the pinion to point to the output of the x-fer case. Actually just slightly below pointing exactly at it so to make up for the torque of the axle when accelerating.

You probably have already heard all of this information, but I offer it as it may be of help.

What we have done before was do the SYE kit and get a front CV shaft from a chevy and shorten it. That has worked pretty well and fairly cheap.

Cool, I was looking at the SYE because eventually i'll end up going with a long arm flex down the road after I break this or grow out of this lift =) For now i'll just drive careful and hopefully get the SYE and a new driveline fairly soon, Thanks for the information!

Got any kits that come complete for me to do it myself? I'm pretty mechanical savy, just dont want to get a kit that I that will cause me to stop the process in the middle of fixing it to get something they forgot.

you can get the tom woods sye and drive shaft combo. goto www.4xshaft.com

You have a number of options:

Your vibes are caused by your pinion angle. Without getting into a lengthy explanation, I'll let the pro's explain:
http://4xshaft.com/driveline101.html


1st (and best IMO) buy the SYE and DS. The SYE will allow you to keep the T-case in it's stock location and will allow you to cure the vibes, for the most part, at the same time. It's expensive and requires some skill to do, but is probably a 7 on a 1-10 scale. With an SYE you'll need the pinion to be in the following orientation to the t-case output:
http://4xshaft.com/images/cv_angle.gif

2nd, get the t-case drop and adjust the pinion angle properly. You'll lose 1" of ground clearance in the middle but could completely solve the vibration problems for under $100. Honestly, you could do it for the price of the bolts and some washers, but, that looks pretty gheto is is really a band aid fix. You don't need a longer DS as noted above. If you're not doing an SYE right now, don't waste the $$$ on a longer DS. You'll be kicking yourself when you throw it in the trash after the SYE install. Without an SYE you'll need the pinion in the following orientation to the t-case output.
http://4xshaft.com/images/2joint_angle.gif
http://i3.photobucket.com/albums/y87/butch6924/Smilies/fast.gif