[hotnutz]

For the past two weeks my jeep has been idle as i added coil spring spacers and a hack n tap. Yesterday i got it to the drive shaft shop so they could build me a DS. Well 5.25" with a hack n tap did not work for them, they built it but still got bad vibes. So i went home in front wheel drive thinking about how to straighten this out. This morning I put my T-case drop on and drove it. It still seems to vibe worse then it did with out the H&T on 4" with stock shaft and T-case drop. I'm about to take it to him and let him drive. Any other recomendations. I do have 1" spacers i could trade my 1.25". Ive been on bike for two weeks and butt is killing me

[RLD831]

You may have done the hack and tap wrong. I've never gone that route, but it seems like if it gets messed up, it's not fixable since the output shaft was cut. If you're going to drop the transfer case skid anyway you can put a new slip yoke on the TC, otherwise I'd suggest going with a SYE.

[moparjunkee]

Did you install adj uppers and adjust the correct pinion angle? This should be your next step if you haven't. If you already have, then maybe play with your pinion angle a little bit and see what happens.

[hotnutz]

not sure what those are gonna have to check into it. thanks

[RLD831]

"adj uppers" are adjustable rear upper control arms. If you lengthen them they will rotate the top of your axle towards the rear which tilts the pinion upward because the pinion should be pointed directly at the transfer case output shaft so the pinion and driveshaft are on a single straight line.

[hotnutz]

thanks, know of a write up to adjust them?

[Varnish]

http://www.stu-offroad.com/axle/pinion/pinion-1.htm

[Jerry Bransford]

It's highly doubtful the hack n' tap is the root cause of the vibes. Exactly what kind of driveshaft did you install after installing the SYE and exactly how did you set up the rear pinion angle?

[Death_Valley_TJ]

Did they build a CV style DS or did they just make a longer statndard u-joint style DS. If you have a CV style DS then you have to tip the rear axle so the pinion is aligned with the DS. For this you will need adjustable uca's. If they didn't build a CV style DS then you will probably not ever get rid of the vibes.

Edit: Jerry beat me to it. I type too slow.

[hotnutz]

Thanks varnish, thats actually a page i read before posting, it doesn't show how to manipulate the adj arms.

[hotnutz]

I is a cv ds

[hotnutz]

Do i buy these arms or do i already have them?

[Jerry Bransford]

Originally Posted by hotnutz

I is a cv ds

Good... and the answer to my second question is?

This is how your rear pinion angle SHOULD have been set up...

[Varnish]

Originally Posted by hotnutz

Thanks varnish, thats actually a page i read before posting, it doesn't show how to manipulate the adj arms.

Depends on which arms but they are pretty self explanatory. The stock arms can't be adjusted (outside of adding a cam bolt but most folks don't do that) because they are stamped steel. You need aftermarket upper control arms that are made to adjust - they have a threaded portion with a lock nut. Some of them you can adjust while they are on the vehicle and some you need to disconnect one end or the other. Lengthen the arms to point the pinion angle up higher, shorten them to lower the angle.

For example...

[hotnutz]

thanks, I guess i needa buy some. Whats a good price for em?