anyone that lives in sacto area down to test drive a vibe situation? im all out

[blondejoncherokee]

i was wondering if anyone in the sacramento area could come by for like 20 mins one day who wouldnt mind test driving my xj with me and maybe doing a quick check of anything i might have missed. i still have vibes, and i dont know where to go anymore, and maybe one of you more seasoned vets could maybe have a better idea after a quick test drive and a look at the steering and maybe the driveshaft angles. im confused anymore. ive replaced so many parts and still stuck with vibes, just not as bad anymore. i would totally give a 24 pack for sure and maybe some cash if you could point me in a good direction. im trying to avoid a sye if i can, but ill gladly do that if you guys think thats my only option, but i want to get any other possibilities outta the way first.

do motor mounts have a break-in period? it started to happen significantly worse after i did the first motor mount

-i have done the lca bushings,
- driver side uca with frame end bushing on it.
-both hubs are new
- 2* shim under rear packs to account for axle wrap.
t case drop
-tires balanced
-new motor mounts and newer but used and in better shape tranny mount
-new doetshe shocks from rustys(could these shocks just be garbage? and giving me vibes) with rear bpe's
-yj slipyoke and retubed rear driveshaft
-pulled front shaft off for a while, still have vibes.
-brakes are good, new rotor on driver side with the newer hub with the 297 shaft from a 96
-jks quicker discos
-stock toe hooks with the better bumper mounting and more mounting points that go further back
- new zj tie rod
-ball joints seem good, no play in wheels from what i can tell
-ive done my alignment a few times, but i was thinking maybe to take it in to a shop, maybe im not on point with the alignment and maybe having the tires checked agian for balance???

 

[Slonopotam]

Is it just your sterring wheel vibrating or the whole jeep ? You have to be able to feel the difference.

I hope you already read this one.
http://www.4xshaft.com/driveline101.html

 

[jeepme]

JUST DO THE SYE like you have been told on your other post!!!!!!!!!!!!

 

[Phil]

Have you pulled the rear shaft and driven on the front only? Make sure to cap the tailcone so you keep your fluid.

I drove mine front only at ~65 MPH when it was still open, no problem. Well, except that I was cold and wet.

 

[blondejoncherokee]

im sorry to keep posting and bothering you guys....im just trying to not spend any more money on the vibe situation than i have to. ive already spent all the time and money i had for rear locker and better uca's and a better trackbar, etc... on just trying to get it driveable first.
there is nothing in the steering at all. entire veichle kinda vibes bad above 60 and im gonna do the sye. gonna order it from porc prob tomorrow or thurs. shim it 2-3 degrees under the driveshaft angle and swap out the shims facing forward and swap in some shackles etc... i just want to make sure that there isnt another bigger thing im missing cuz my angles are great and everything up front is new and it used to not vibe. like maybe if one of guys drove it with me for a sec you'd know if it was driveline vibes or something else...basically im afraid that the sye might not fix it and id still have vibes if there was a bigger issue...plus ive only met one or two seirra chapter guys so itd be cool to meet more of you dudees adn and i want my heep ready for the slickrock/deervalley run. im more a tatooed drunk punk that likes jeeps...

 

[blondejoncherokee]

maybe i should make this post after i install the sye and only if it still vibes then...

 

[Slonopotam]

retubed rear driveshaft

Why it was retubed ? Are you sure it was balanced afterwards ?
Is your driveshaft running on the last inch of travel after you lifted ?

You can stop spending money and start collecting data and putting it into this thread, like all your driveline angles. That would help.

I am definitely not an expert and I do not live in Sacramento, so I am not saying I will be able to help, but I can share my experience. I had vibes so strong that my teeth were shattering and my angles were "normal", as everybody said. Everybody but Tom Woods. He said it was "not unheard of".

 

[blondejoncherokee]

oh, ya, it was balanced and my tcase output it about 6.5-7* with the drop and my pinion angle is about 5.5-6.5. the longer xj 44 pinion and the yj slipyoke gave me back all of the spline i had sticking out from before. now i have barely an inch out...i had it retubed to be an inch longer and then swapped in an xj 44 in jan and had it shortened an inch again, im stupid as hell for that one...my vibes are bearable, and not constant, but any up hill accel is really bad basically and just about anything over 60 can be pretty bad. back in december i was going 80mph with no noticable vibes on the exact same setup, but then i changed some stuff, got vibes, put it all back and still had vibes...

 

[Slonopotam]

had it shortened an inch again

Was it balanced after that ?

any up hill accel is really bad basically and just about anything over 60 can be pretty bad.

Sounds like an axle wrap. What do you have for leaf packs ?

but then i changed some stuff, got vibes, put it all back and still had vibes...

More details, what did you change and what you put back ?

I will check at home what my angles were when I had vibrations.

 

[Slonopotam]

my tcase output it about 6.5-7* with the drop and my pinion angle is about 5.5-6.5.

These 7*, is it between ground and t-case or is it the difference between t-case and driveshaft ? If these angles are to ground, what is your driveshaft angle ?

When I lifted the angles to ground were
drive shaft ~20*
transfer case ~5.5*
differential ~6*
The vibrations were severe.

 

[blondejoncherokee]

measured from the output by placing a socket on the slip part of the slip yoke and then an angle finder upside down on that. roughly 6.5-7*
at the pinion placed an angle finder under a socket from the u joint cap. roughly 6*

bought the xj with a 3.5" 5 leaf rustys pack. on 33's swampers. no vibes. long drives and no vibes. nothing.

then it started. i wanted to lift the rear a bit. threw on some RE boomerang shackles. got vibes. guessed at a 6* shim and kicked the vibes back to 65mph. that wasnt good enough for me, i used to go 85 mph no vibes.

so i pulled the shackles and tried add a leafs to get that extra inch in the rear. . it added an extra 3.5 inches and just for the heck of it i tried it and the vibes were horrendous. tried a 4* shim, still really bad.

pulled everything off and went back to rustys 3.5 packs. okay. well now i still had vibes. then i got pissed.
finally went and bought an angle finder and measured. well with the tcase drop and 3.5 springs the angles were good, it had the drop when i bought it. i could have also swapped on the 4* shim and pulled the drop. tried that. vibes were still really bad.

so now im back to the drop. remeasured and put in a 2* shim. that leaves me with the current angles with the t case output roughly 7, and the pinion from my mesurements around 6, maybe 6.5*

do you think the old worn leaf packs are causing bad axle wrap?
is there a point where i should replace them?
like maybe some new 3.5" leaf packs?

or can i keep these old leaves and go with a sye and be alright?

maybe the constant taking apart of the leaf packs fatigued them, or maybe it was just their time to be shot....

 

[blondejoncherokee]

by the way a buddy told me that i might need an adj. track bar. but im only at 3" would the RE basic adj. one be a good idea? maybe that will help?

 

[blondejoncherokee]

ok. i think i have a buddy that has the flange for a hack and tap and i can go by RE and buy the seal and housing. im thinking an adj. trac bar would be good too

 

[Slonopotam]

at the pinion placed an angle finder under a socket from the u joint cap. roughly 6*

When you put angle finder on the non-slip part of the driveshaft, what does it show ? Take all the readings when the jeep is parked at the same place.

i might need an adj. track bar. but im only at 3" would the RE basic adj. one be a good idea? maybe that will help?

Solve one problem at a time. This is especially true if your resources are limited. Your vibes will destroy u-joints and you will be in for a whole lot of fun more.

How does your lifted jeep run now without adjustable trackbar, does it have the axle mount redrilled? When you put a lift on, either the trackbar must become longer, or the axle mount must be modified. Otherwise your front axle will move to the left. Trackbar has no effect on vibrations, unless it falls apart.

ok. i think i have a buddy that has the flange for a hack and tap and i can go by RE and buy the seal and housing.

I hope you realize you will need a CV driveshaft too. It is funny, but you never mentioned this. I also hope you can cut straight.

 

[jeepme]

Yep remember you will need a new drive shaft (CV style)to go along with the SYE. You can get one from RE or any good driveshaft shop. I prefer Tom Woods but that just me.

 

[blondejoncherokee]

by non slip part of driveshaft do you mean the ear of the yoke at the t case? that would be the same as the driveshaft.
thats why i measured the slip part....to get the angle of the u joint. it was 7*. the angle of the u joint at the pinion was roughly 6.5. driveshaft was roughly 14. i did this all in my garage in one place

im at 3", bought it that way with 33's, i swapped in 31's for more rpms ont he freeway.

the trackbar is a new stock track bar i got for nothing... i plan on going adjustable. no axle mount redriled. wasnt enough difference in the placement to make it worth drilling a hole, it would have been too close.
and im no stranger to a cutting wheel.

ive thoroughly read a few hackntaps online, im ready for it. ive done some worse cutting and drilling and tapping in worse places on two of my previous scouts. i never had vibes in a scout, i guess i just got dumb lucky that way.
i have some stuff already for the sye an auto front driveshaft, some rough country 2" shackles to point up the pinion and give me more lift. center pins and 2* and 4* steel shims.

but anyway, could i need new rear leaf packs if they wrap too bad?
i

 

[blondejoncherokee]

got a flange on the way. gonna stop by RE and get the seal and seal housing unless anyone knows a better place to get it from...
do you guys think the old springs need to be replaced...

 

[XJensen]

Did you drive it without the rear driveshaft?

If you are going to do the hack-n-tap anyway drive it when you are done and see if they went away. Adjust then test, repeat. Do not change very must before testing or you will not know what helped and what did not.

 

[GauchoMD]

I didnt read every post (some were pretty long), so I'm sorry if I missed this but I had a similar problem and it was a worn rear u-joint... Mine viberated more with increased speed, especially on the highway and while accelerating (or stepping on the gas at all) and mostly went away when I let of the gas entirely. It was a very cheap and easy fix.

 

[blondejoncherokee]

the u joints are brand new. like prob 40 miles at most on the u joints and thats prob an exageration....and im gonna take off the driveshaft maybe tonight and tape a 1 liter bottle over the cone and take it on the freeway... im getting ready to do the hack n tap too, prob in a week or so when i have a free sunday and make sure i have all the neccesary parts. ill keep ya posted on my progress. what does a worn t case chain have symptoms like anyway?