I recently installed a hand-me-down lift (3.5" RE) on my TJ. It come with new lower control arms, a track bar riser, new shocks and springs, and a new rear drive shaft with SYE. The car runs fine below 20MPH but when I get to about 25-30 it violentely vibrates (death vibe). The car the lift was originally installed on had a rear Dana 35 however mine has a 44 would this effect the drive line and cause the vibe, or is it caused by something else like misalignment?

thank you

p.s. pleasE lol

did you get an alighnment done after the install?

No that's happening tomorrow (fist opening they had). The vibration happens more severely when the drive line is under load i.e. excel and breaking. which makes me think that the drive shaft is the issue. Also my car has been misaligned before and the vibration hasn't been as severe.

Check to make sure your track bar relocation bracket and bushing bolt is tight. Also with new lowers your castor could be off. Are the lower comtrol arms adjustable?

They unfortunately aren't, Im going to check the track bar but would it cause a crazy vibe like that?

check the body side track bar mount and make sure its tight i had the death wobble then it turn out it was that..

The RE 3.5 lift comes with fixed lower control arms. I see where you installed a SYE and CV driveshaft, but you didn't say anything about what you are doing for upper control arms or if you used the TC drop. First thing would be to get an alignment. Then check your track bars. Then visit Tom Woods Wed site for chart that shows proper rear driveshaft pinion angle. What Jeep are we talking about and if you do not have an automatic locker in the front axle, remove the rear driveshaft and drive the Jeep in 4 wd. If ride is smooth, you have a pinion angle problem.

Braking wouldnt be a driveshaft issue unless you down gear and use an engine brake

Im going to check the track bar but would it cause a crazy vibe like that?

Absolutley, the "knock the fillings out of your mouth" death wobbles are very often from loose or sloppy track bar issues. Also look closer at the track bar re-lo bracket, if the hole is the least bit out of round this is very likely your problem. if it is, you'll have to drill it out along with the bushing on the track bar and get a bigger bolt for a tight fit.

Are you having the "death wobble" where it feels like the front wheels are coming off the ground or bouncing OR are you having driveline vibrations from a wrong pinion angle on the rear axle? Seems like some people think it is one and some think it is the other. Either way its fun.

here is a picture of the drive line maybe you can tell me if the angle would cause vibe or not.

http://i50.photobucket.com/albums/f328/heliarker/DSC_0015.jpg

http://i50.photobucket.com/albums/f328/heliarker/DSC_0019.jpg

http://i50.photobucket.com/albums/f328/heliarker/DSC_0020.jpg

http://www.4xshaft.com/images/cv_angle.gif

Personally, I think you need to tweak your pinion angle some. However, I don't think your vibe is caused by this. As I said before, you can always remove the rear DS then drive Jeep in 4hi (careful if auto locker in front axle) to determine if your pinion angle is even an issue. Did you do a front end alignment? Did you check the track bars and brackets as discussed? Give us an up date on where you are in the process, please.

**EDIT** I wasn't going to say anything, but I changed my mind. I am concerned about the fact that sitting on level ground you have little if any spline exposed from the slip yoke of the DS. How compressed is this DS? I say remove the DS and go for a test drive before you do anything else. Others can correct me if I am concerned about nothing.

Hey, you have a nice "Beemer" sitting next to the Jeep, you can afford some adjustable rear uppers to take care of the pinion angle. This may or may not be your problem but it needs to be addressed anyway.

I made an edit to my last message. Am I concerned about nothing?

I can't help but notice that you drive line looks like it is colapsed all the way, I think Little Jeep is on to something.

Hey, you have a nice "Beemer" sitting next to the Jeep, you can afford some adjustable rear uppers to take care of the pinion angle. This may or may not be your problem but it needs to be addressed anyway.

LOL:D

hey the beemer is 4WD, real good in the rocks... I messed with the track bar and it's about 60-70% better vibration wise. Ill have a drive line shop look at my pinion angle and see if i need to mess with it or not. thanks for all the help!!!

Wait a minute- the track bar has absolutely nothing to do with driveshaft vibration, so if you think it's better it must be in your head. That's what happens when you title a thread like you did and get two sets of people thinking of two different problems.

Anyway, your rear driveshaft situation doesn't look good. Your pinion angle is at least 6 degrees low and rotating it to the proper angle will kill off what little bit of driveshaft compression you have left. The driveshaft will become a bumpstop if it isn't already. It'd probably be OK with a 35 but the 44 is longer in the pinion. So, you can move the axle back, move the powertrain forward, or have the driveshaft redone when the pinion angle's fixed. Pick your poison. :flipoff2:

heliarcer after you talk with a driveline shop about that compressed DS, and your pinion angle (two issues), let us know what they say. Based upon the photos, you will not be able to adjust the pinion angle because you already have a compressed DS. Normally, you would have a couple inches of spline exposed. Your DS is short, so maybe a inch exposed is all you need? I am not sure what would be cheaper, work on the DS, or ditch the hack N Tap SYE for a heavy duty one, or even a super shorty. I assume that the HnT SYE was installed in the correct location? I am lazy and don't want to read, did you say you are, or are not using a TC drop. If you are using a TC drop, maybe you could ditch it and add some adjustable upper control arms. However, your DS is such, I am not sure that you will have space needed to do this.

One of my friends on ohio 4x4 just fixed his problem....loose yoke nut.TIghtened it and got rid of all the vibrations.

Spend more money and get a larger lift. Then you can adjust you pinion angle and your drive shaft will spread a little. Try coil spring spacers, this may be the cheapest way to go. (If not you can sell them to a newbie). I have a set on my coils along with my lift.
I had a front end death wobble also on my XJ, really don't know why. I corrected the problem when I installed a heavy duty trackbar, a Steering conversion, and a better dual steering stabllizers.

Good luck with that

Steering stabilizers are useful but they treat the symptom, not the cause.

Steering stabilizers are useful but they treat the symptom, not the cause.

If you read the post up to yours,you would realize everybody thinks it is his driveshaft causing the vibes.Not death wobble.:flipoff2:

Steering stabilizers are useful but they treat the symptom, not the cause.

Bullshit.

Bullshit.


Really, maybe you can explain to me how replacing, or even better yet, adding another steering stabilizer will FIX your death wobble or vibe problem. Notice I said FIX and not hide or mask the real problem.

So what your saying is this, you have a wobble or vibe problem, you throw on a beefy stabilizer or two, your wobbles or vibes then go away. Problem fixed? I call Bullshit.

Is there enough room between the slip yoke and the drive shaft? Looks like under acceleration the pinion would torgue up, making the distance between the slip yoke and drive shaft even shorter, possibily bottoming out on the drive shaft and creating your vibration?

So what your saying is this, you have a wobble or vibe problem, you throw on a beefy stabilizer or two, your wobbles or vibes then go away. Problem fixed? I call Bullshit.

No, that's not what I'm saying. Tell you what, why don't you go fix front ends for 15 years, then you'll see what I'm saying. Until then you don't know shit so shut up. :flipoff2:

Take your stablizer off and go for a ride, to the parts store.
I did that after buying a new one, and it didn't come with the correct hardwear. Thanks to Ranco for not comming with the correct shit. :mad3: That's the exact wobble I had, later on.
I belive my problem was from the hardwear mount on my drag link.
The Ranco worked great for about a year(had used some old parts and fabed spacers). Then my death wobble started. Pior to the steering up grade.

So like I said I made other up grades at the same time when I put on the two stablizers in. Heavier full lenth tie rod, and adjustable heavy duty trac bar with a new frame mount. So I didn't mask my problem!

*UPDATE* I removed the rear drive line after I noticed that it was coming UNDONE!!! The bolts that had held it to the SYE had worked them selves about 1/8 an inch out which started caused a lot of my vibe to come back about a day after I fixed the track bar. I drove the car all-day today with out the rear drive line and there was no vibration, in-fact it rode better than stock because of the stiffness. While I was out I bought lock washers, "nylock" nuts and "locktight" to ensure that never happens again! I also bought longer bolts and 1" nylon bushings to put between my skid-plate/T-case cross-member and frame rails to hopefully get the pinion, more like the drive line, at a more desirable angle.

*UPDATE* I removed the rear drive line after I noticed that it was coming UNDONE!!! The bolts that had held it to the SYE had worked them selves about 1/8 an inch out which started caused a lot of my vibe to come back about a day after I fixed the track bar. I drove the car all-day today with out the rear drive line and there was no vibration, in-fact it rode better than stock because of the stiffness. While I was out I bought lock washers, "nylock" nuts and "locktight" to ensure that never happens again! I also bought longer bolts and 1" nylon bushings to put between my skid-plate/T-case cross-member and frame rails to hopefully get the pinion, more like the drive line, at a more desirable angle.


Glad to hear it.

No, that's not what I'm saying. Tell you what, why don't you go fix front ends for 15 years, then you'll see what I'm saying. Until then you don't know shit so shut up. :flipoff2:

Then what are you saying?:shaking:

Take your stablizer off and go for a ride, to the parts store.
I did that after buying a new one, and it didn't come with the correct hardwear. Thanks to Ranco for not comming with the correct shit. :mad3: That's the exact wobble I had, later on.
I belive my problem was from the hardwear mount on my drag link.
The Ranco worked great for about a year(had used some old parts and fabed spacers). (Until your REAL problem got worse!)Then my death wobble started. (Hah)Pior to the steering up grade.

So like I said I made other up grades at the same time when I put on the two stablizers in. Heavier full lenth tie rod,(Size/O.D. of tie rod has NOTHING to do with death wobble, but worn out ends can) and adjustable heavy duty trac bar with a new frame mount.(BINGO!) So I didn't mask my problem! If you say so.

*UPDATE* I removed the rear drive line after I noticed that it was coming UNDONE!!! The bolts that had held it to the SYE had worked them selves about 1/8 an inch out which started caused a lot of my vibe to come back about a day after I fixed the track bar. I drove the car all-day today with out the rear drive line and there was no vibration, in-fact it rode better than stock because of the stiffness. While I was out I bought lock washers, "nylock" nuts and "locktight" to ensure that never happens again! I also bought longer bolts and 1" nylon bushings to put between my skid-plate/T-case cross-member and frame rails to hopefully get the pinion, more like the drive line, at a more desirable angle.

Heliarcer..... it is hard to tell from the photo.. but it appears that the slip yoke on the driveshaft maybe bottomed out on spline (the middle part of DS that expands and contracts). Trying to correct the Pinion angle is only going to make this worse. Your Pinion angle needs to be tweaked...... but I think a serious look at that DS length is needed as well.

Is there enough room between the slip yoke and the drive shaft? Looks like under acceleration the pinion would torgue up, making the distance between the slip yoke and drive shaft even shorter, possibily bottoming out on the drive shaft and creating your vibration?

I have been saying this exact thing for days... Unfortunately, I don't think the message is being received. :shaking:

Heliarcer..... it is hard to tell from the photo.. but it appears that the slip yoke on the driveshaft maybe bottomed out on spline (the middle part of DS that expands and contracts). Trying to correct the Pinion angle is only going to make this worse. Your Pinion angle needs to be tweaked...... but I think a serious look at that DS length is needed as well.

This is exactly what a few others have been trying to get him to see.As for the others debating steering stabilizers.Go start your own thread in chit chat or newbies.They have nothing to do with this guys problem.:shaking:

Hello, drive line not death wobble :flipoff2:

definately check that ds. You take off fast and that could mess alot more shit up than a wobble could. I busted a pinion in half and cracked my xfer case in half with about that much compression.. climbing sand dunes while doing it.