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ATL ZJ
12-28-2004, 12:45 AM
A little background: I bought a Waggy 44 setup for an XJ in July or so, and put it under my ZJ. I dealt with a little DW at first, but got it more or less sorted out so it rode fairly well. Never great, but liveable. I'm running Kevin's arms with the 2 fixed lowers and one adjustable upper in the front.

Recently, I've been getting some nasty shimmy over bumps. This is lateral sway, not deathwobble. For example, over a speed bump, the Jeep will lean left and right hard. I can't take them at over 5 mph. I am talking about the little ones, not the bigger gentler ones. The front swaybar is connected with cheapo discos. The welds holding the truss onto the cast iron of the pumpkin did break while wheeling in November, which broke a shock and tore up the front driveshaft. The truss was reattached correctly however, using the proper welding method in which the cast iron was heated and reheated during the welding process.

The bushings are getting torn up because the front lower CA brackets are so misaligned. I am getting hints of deathwobble sometimes, and other times it breaks out into mild DW, but it really isn't that bad on the scale of all that I've experienced.

The front shocks were just replaced with crap hydros but those may be insufficient. I am getting a lot of floating up and down over bumps. This bouncing can become as intense and puckering as mild deathwobble. This may just mean I need nitrocharged shocks though.

The only 3 things I can think of that I haven't already checked that would cause the lateral shimmy/DW are:

1. Bent trackbar
2. Incorrect caster?
3. Misaligned lower CA brackets (see pictures)

http://img.photobucket.com/albums/v125/atlzj/Jeep/zjsusp_0031.jpg
http://img.photobucket.com/albums/v125/atlzj/Jeep/zjsusp_0030.jpg
http://img.photobucket.com/albums/v125/atlzj/Jeep/zjsusp_0028.jpg
http://img.photobucket.com/albums/v125/atlzj/Jeep/zjsusp_0034.jpg

Matt B
12-28-2004, 02:19 AM
when i had the 4" with stock control arms i had DW even though everything was new, i just set the front toe out just a hair and that really stabilized the front...just thought you it might be helpful.

LouisianaZJ
12-28-2004, 04:03 AM
sounds like it could be bumpsteer, how is your steering setup?

ATL ZJ
12-28-2004, 04:36 AM
There are other issues aside from the deathwobble. I already set the toe slightly out. That helped some.

I have a little bumpsteer. I'm running an inverted T. The trackbar and draglink angles are pretty close, so when I do get bumpsteer it isn't bad at all. The lateral shimmy motion I am describing is not bumpsteer though. When the side-to-side leaning does occur, it's not felt at the steering wheel.

FinlayZJ
12-28-2004, 09:14 AM
I am getting hints of deathwobble sometimes, and other times it breaks out into mild DW, but it really isn't that bad on the scale of all that I've experienced.

Hahahaha.

I don't think a bent t-bar well do that much unless is has made the bushing-end highly misaligned in the mount.

http://img.photobucket.com/albums/v296/FinlayZJ/trackbar.jpg

These two trac bars will act the same way. It's not the bar, but the two end points that matter.

Are your shocks the proper length?
Do you have a steering stabilizer?

What's your caster look like?

http://img.photobucket.com/albums/v296/FinlayZJ/caster.jpg

Are you still at home? I might be able to help if you need it.

JeepinHank
12-28-2004, 12:00 PM
What kind of track bar are you running?

If its a weak one, it may be allowing a bit of movement. Not sure if that would totally explain the problems you're having though.

ATL ZJ
12-28-2004, 02:35 PM
I am getting hints of deathwobble sometimes, and other times it breaks out into mild DW, but it really isn't that bad on the scale of all that I've experienced.

Hahahaha.

I don't think a bent t-bar well do that much unless is has made the bushing-end highly misaligned in the mount.

http://img.photobucket.com/albums/v296/FinlayZJ/trackbar.jpg

These two trac bars will act the same way. It's not the bar, but the two end points that matter.

Are your shocks the proper length?
Do you have a steering stabilizer?

What's your caster look like?

http://img.photobucket.com/albums/v296/FinlayZJ/caster.jpg

Are you still at home? I might be able to help if you need it.

That makes sense about the trackbar. The bushings are aligned in both trackbar mounts correctly. JeepinHank, it's the ORGS trackbar I believe that Kevin sends out with his trackbar conversion so it should be plenty strong. I am running a steering stabilizer. The shocks should be pretty close to ideal. They're 25" extended hydros with raised lower mounts and upper loop shock coversions at the upper mount. The caster looks very much like the picture. If anything, there's slightly too much caster.

Yes, I am at home and do need some help with this. Mainly in replacing the brackets for the lower arms to get them lined up right.

gearhead313
12-28-2004, 04:02 PM
I would look into the track bar as well...

Get someone to get in it and steer it back and forth fairly lightly just to take up any play in the steering. As someone does that check out the track bar and see if anything is moving, if the track bar is moving in the either mounting location.

Also, ANY bad joint in the steering could possibly cause problems. Check the pitman joint, down the drag link to the center link joint, then the tie rod ends. You never know if something miight have gone bad without you knowing.

Let us know if you find anything.

Nordic1
12-28-2004, 06:17 PM
I was getting mild DW as well... I seem to eat the bushings on Kevins TB setup so I am switching to RE's

Pearce
12-28-2004, 07:47 PM
The track bar is set up pretty tight. We fixed that with larger bolts to take up the slop. That one bushing is way out of alignment but it shouldnt really cause that much of a problem. If they are getting torn up though it may. I would also look at the body side joints and see how they are doing.
Also try having someone turning the steering wheel while you look at all the joints from body side to axle. Get them to do it in long turns and quick short turns. Look at the hubs as well. If you want to drive up early Friday morning I can also look at it. But give me a call first, I have company for the weekend.
One more thing, when I ran with only one upper like kevins, it seemed a little more loose to me. But there are many people running that way and don't see a difference.

Kraqa
12-28-2004, 08:25 PM
i bet its those BOOGER welds.

hmm seems funny i don't know what to say. i hope you figure it out.

ATL ZJ
12-29-2004, 01:45 AM
The track bar is set up pretty tight. We fixed that with larger bolts to take up the slop. That one bushing is way out of alignment but it shouldnt really cause that much of a problem. If they are getting torn up though it may. I would also look at the body side joints and see how they are doing.
Also try having someone turning the steering wheel while you look at all the joints from body side to axle. Get them to do it in long turns and quick short turns. Look at the hubs as well. If you want to drive up early Friday morning I can also look at it. But give me a call first, I have company for the weekend.
One more thing, when I ran with only one upper like kevins, it seemed a little more loose to me. But there are many people running that way and don't see a difference.

I had a friend turn the wheel this afternoon. There is some movement in the upper trackbar bushing. The whole axle moves right and left quite a bit during short, quick turns. The axle is really loose under there. I think removing the lower CA mounts, replacing them with properly aligned ones, and replacing the bushings that are worn out is very necessary. And getting an upper on there ASAP is very necessary. The bad thing is that there is nothing in the entire front suspension and steering that can be eliminated as a possible cause for all this. It might be that everything is slightly out of alignment, loose, or somewhat worn and the result is a Jeep that is hell to drive daily. I did have miserable DW at first, which probably took a lot out of the life of bushings and TREs.

Pearce, I am sending you a PM about Friday.

CruisinGA
12-29-2004, 02:28 AM
[quote=ATL ZJ]I don't think a bent t-bar well do that much unless is has made the bushing-end highly misaligned in the mount.

http://img.photobucket.com/albums/v296/FinlayZJ/trackbar.jpg

These two trac bars will act the same way. It's not the bar, but the two end points that matter.


Cam, wasn't sure you'd get my email, so I figured I would post up here.

Yes the two ends are what matter, but if a rod that is made to be length X, is bent, it becomes <"Length X".

A TR that is bent enough or has toasted bushings or a combination, could affect the location of the axle side to side. Your CA mount pics show rods entering the axle at an angle, which if your mounts are welded straight leds me to believe your axle is not sitting centered under your truck.


Just come down to the cruiser shop this week, we'll get you some cruiser parts under there and solve the root of your problems. ;)

Bailey

ATL ZJ
12-29-2004, 03:23 AM
I wish it was just a bent and therefore shortened trackbar that was causing the misalignment of the arms in the mounts. But the mounts are angled inward on both sides. The arms want to angle inward also, so there's a conflict of interest there that isn't affected by the axle just being shifted to one side. I'll add another wonderful illustration to this thread to show what I mean:

http://img.photobucket.com/albums/v125/atlzj/Jeep/d44LAdrawing.jpg

I'd put a TTB Dana 28 under my rig before I swapped Cruiser parts in. ;)

ATL ZJ
12-31-2004, 03:47 AM
I took some length out of the upper to drop the pinion down and gain some caster. It helped a lot. It's very smooth over bumps now, makes me kick myself for having it so out of adjustment before. I do still need to turn lower control arm mounts, even though adding some caster helped get the angles slightly better, or so it appears.

I had one incidence of DW after the caster adjustment and full trackbar check, including recentering the axle under the vehicle. It takes speedbumps with much less lateral shimmy now. That is nearly gone. But there is still a little play somewhere. I'll realign it tomorrow and put some good gas-charged shocks on. The cheap hydros really do nothing.

Now I'm looking at the play in the bushings of the lower arms and the wear of those bushings as caused by being chewed up by the metal of the brackets. What about needing a camber adjustment? The upper balljoint of Waggy 44s allows for the adjustment of camber, but I never got it set to exactly what it should be. I just got them tight and matched them side to side. Advice?

gearhead313
12-31-2004, 09:54 AM
Camber shouldnt' be an issue... but if you did set it incorrectly, at least correct it and work from there. Just like the pinion angle too. Set it right and forget it. If anything is in question, take care of that first before you start assessing the original problem.

I still think you have a bad joint that you haven't found yet, or a wee bit of play in track bar that hasn't shown up yet.

ATL ZJ
12-31-2004, 07:32 PM
Well today I pulled the shocks and went to the parts store to replace them with better ones. On the way (riding in a buddy's Jeep), I compressed and extended both shocks about 40 times. They had none in stock, so I returned home empty handed. I put the hydros back in, but flipped them. Now they work great. So do they have to be lubricated or run with a specific side up? I thought it was a little strange. Took it over some speedbumps today and it feels just about right. The lateral lean/shimmy is gone.

nathaniel
12-31-2004, 09:35 PM
Well today I pulled the shocks and went to the parts store to replace them with better ones. On the way (riding in a buddy's Jeep), I compressed and extended both shocks about 40 times. They had none in stock, so I returned home empty handed. I put the hydros back in, but flipped them. Now they work great. So do they have to be lubricated or run with a specific side up? I thought it was a little strange. Took it over some speedbumps today and it feels just about right. The lateral lean/shimmy is gone.

Hydros are almost always can down. And almost always specific about direction. That explains why u get dw and are all over the place when going over speedbumps.

ATL ZJ
01-01-2005, 01:42 PM
Hydros are almost always can down. And almost always specific about direction. That explains why u get dw and are all over the place when going over speedbumps.

Yep, it rides like a dream now. At least for being a ZJ on 35s.

KevinF
01-02-2005, 10:12 PM
Glad to hear that it's behaving better for you now, Cam. I suspect that the lower bushings out of alignment are the root of the remainder of your problem. I'm more than happy to sell you some rubber mounts to replace those chewed up ones at my cost if you shoot me an e-mail. Getting those brackets into alignment is key to a smooth transition over speed bumps, though. The bushing housing will walk sideways over the rubber if the center is anything more than a smidge out of "perpendicular to force", which will cause the arms to slightly change length, causing some major caster changes as well as pinion changes as well. I'll also send you a set of replacement bushings for the track bar at my cost if you would like me to. The taller the Jeep is, the quicker those bushings wear.

HTH,
Kevin

ATL ZJ
01-03-2005, 02:11 AM
Glad to hear that it's behaving better for you now, Cam. I suspect that the lower bushings out of alignment are the root of the remainder of your problem. I'm more than happy to sell you some rubber mounts to replace those chewed up ones at my cost if you shoot me an e-mail. Getting those brackets into alignment is key to a smooth transition over speed bumps, though. The bushing housing will walk sideways over the rubber if the center is anything more than a smidge out of "perpendicular to force", which will cause the arms to slightly change length, causing some major caster changes as well as pinion changes as well. I'll also send you a set of replacement bushings for the track bar at my cost if you would like me to. The taller the Jeep is, the quicker those bushings wear.

HTH,
Kevin

Kevin, thanks for the offer. That sounds correct as to what's happening with those lower arms. It's doing fine now, so I think I'll wait until summer when I get the time and equipment to turn those mounts myself and just replace the bushings then. And the trackbar bushings are still fine. But I do need a replacement bushing for the frame side of the tri-link where it bolts up to the crossmember. On the passenger side my turndown melted it before I could move the exhaust out of the way. Is there a good source for one of those or would I need to go through you? Thanks again for the help. The system is working great now that I've worked out all the problems caused by installation hangups.