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Apocalypticsurf6

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Discussion starter · #1 ·
So about 2-3 weeks ago I did some serious offroading down in the Jersey Pine barrens and ever since have been experiencing some horrible death wobble. I have a 04 Rubicon TJ, 4" shortarm suspension lift, 2" transfercase drop. Havnt gotten around to getting a new rear ds yet. I have a OME steering shock and up until now it has eliminated all death wobble but as soon as I pulled out of the woods I had the worst death wobble and its still persisting. It usually occurs as I shift from 3-4 and if I downshift back to third and let it drag for a couple seconds it goes away. I thought maybe it was my tranny mount but it looks fine. My factory motor mounts however look like the rubber has pulled away from the metal collars and is saggy rearward about 3/4 of an inch or so(pictures soon). I'm guessing I need new motor mounts and I'm hoping this is the reason for the wobble. Thinking about going with the Brown Dog CU2883-0, Motor Mounts, Ultra-Flex Rubber. I dont have a body lift at the moment and dont really plan to get one. I do plan to put in a Toms woods rear DS and put my transfercase back to stock, possibly even a 9th Degree tummy tuck.

The question is, do you guys think this is the source of my deathwobble (it sounds like my drivetrain is bouncing while its wobbling) and should I go with factory height mounts or something higher? I read in another thread someone recommending 1" MML for someone with a 4" suspension lift like me, this confuses me as I thought you only do a MML if you do a bodylift
 
Discussion starter · #2 ·
The one with the yellow spot on the mount is the driver side, with the red wire in front is the passenger side. there appears to be a gap in the front of both mounts with part of the bushings extending past the collar rearward. Please let me know how shot these are, if I need to replace them I will order the mounts right now but money is not an abundant possession so if they don't need to be changed that would be great
 

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#4 ·
Pull your transfer case skid (after supporting the rear of the engine) and see if you ripped your transmission mount in half. I would replace the motor mounts also. Death wobble is a suspension issue, not a motor mount issue, and if you can get rid of it simply by down shifting, it isn't death wobble. (Have your wheels balanced). If you have plans to do a small body lift and tummy tuck, then 1" motor mounts from Brown dog make sense, if not just use stock mounts.
 
Discussion starter · #5 ·
Well it feels and behaves like death wobble but I am fairly certain is it originating from the driveline. I think the vibrations are being transferred into the steering. Think I'm just going to order a tranny mount as that was my first thought of what might be broken. Think im going to order motor mounts also, just not sure if I want rubber or poly bushings. I love a tight crisp response and don't really mind a little vibration, as long as its not severe. Any recommendations on tranny mounts? Will probably stay rubber for that since it works with both style mother mounts.
 
Discussion starter · #7 ·
Well just got done installing everything. Went with the poly brown dog MM. Added the slightest vibration at idle only, not annoying at all. Used a Crown OE rubber transmission mount. I cant get over how how transmission feels now, it shifts beautifully. However, I am getting just as much if not even worse death wobble, its violent and I'm very worried. The old transmission mount was actually fine, the motor mounts looks a little shitty but not bad. So either one of my tires is way out of balance or my steering linkage is screwed up(seems fine). I still dont understand what would cause this to happen like someone turned a switch on, going to get my tires re-balanced tomorrow
 
#8 ·
Just as Water Dog suggested, death wobble is suspension related, not trans or motor mounts.

Do a dry steer test with a buddy and check all the tie rod ends for play. Check both ends of track bar. Check your control arms. Check your ball joints and unit bearings.
 
#9 ·
I would lift your front end off the ground and check the ball joints if those are okay i would then check the Track bar/bolts, drag link, & tie rod using a dry check turning the wheels.

Also make sure there is no mud/sand stuck in the inside of your barrels.
 
Discussion starter · #10 ·
Well just got the tires re-balanced, that was it. My steering is the cause, thinking about upgrading it now, possibly to the gen-right hi-steer kit or something like that. Would it even be worth trying to fix considering its all crap factory steering components? Any recommendations for an upgrade kit? Unfortunately I dont know enough about steering components to know what to look for as far as fixing it. I'm above average mechanically but there is still a lot I dont know. Aftermarket systems look pretty straight forward but the factory "y" steering system is a bit confusing
 
#14 ·
^^^ thats the one. or for under $150 you can get a ZJ tie rod

moving away from the inverted Y setup is known to cause bumb steer in most aftermarket setups. i looked into it for a while and there is too much effort to make it work right with minimal gain. I went with sway bar relocators and raised the tierod on the driver side to the top side of the mount. gains enough that i dont need it any higher
 
Discussion starter · #15 ·
Just spoke with my local machine shop guy that happens to be the best jeep expert in the state, he was recommending that I only replace my tie rod and get it all realigned. Anyone think this may be enough or should I get all new linkage? Honestly would really love to move to hysteer crossover system eventually but if I can do a quick fix now I can save more towards doing that right down the road.

Oh and just an update, love those new motor mounts, they didnt fix the problem but they fixed another. I had no idea my transmission was so sloppy, it shifts like a brand new car now. No more popping out of 4th 2nd or reverse at all, goes in the first time every time now
 
#16 ·
Ironhead Jed said:
^^^ thats the one. or for under $150 you can get a ZJ tie rod

moving away from the inverted Y setup is known to cause bumb steer in most aftermarket setups. i looked into it for a while and there is too much effort to make it work right with minimal gain. I went with sway bar relocators and raised the tierod on the driver side to the top side of the mount. gains enough that i dont need it any higher
Click to expand...
this
 
#17 ·
Why don't you take a picture of your entire steering system?
Have you gone through your steering and tightened everything?
How about your sway bar at the frame?
Are your tie rod ends tight?
Is the hardware for your tie rods in good condition? Sometimes, the hardware can loosen if it is stripped.
I would suggest that you look closely at all of your steering components as suspect, and check to see if each of these components is tightened adequately.

Page 2 of my 33" to 35" link lists all of the problem parts I dealt with to make my Jeep streetable after upsizing to a 35" tire. 16 months of trial and error.:pc-ouch:
 
Discussion starter · #18 ·
As requested, heres some photos. The only thing that is not tight down there is the upper trac bar connection. There is definitly some play. Looks like the bushing there is long gone, flat as a pancake. I have a feeling I should really replace everything. All the bushing look pretty fried to my eyes.
 

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#19 ·
If you have used POLY bushings in your motor mounts and RUBBER in your transmission mount you will destroy the tranny mount. All three need to be the same material. I would get a poly tranny mount since it is the easier of the two to change. Dennis said to stay with rubber for a reason. Do not mix the two in one system. The poly does not give much, so the vibes will be transferred to the other end and tear up the rubber. All poly does a good job but there will be some vibes. All rubber works well but will not last quite so long - perhaps ten years versus poly lasting somewhat longer.
 
#20 · (Edited)
Apocalypticsurf6 said:
As requested, heres some photos. The only thing that is not tight down there is the upper trac bar connection. There is definitly some play. Looks like the bushing there is long gone, flat as a pancake. I have a feeling I should really replace everything. All the bushing look pretty fried to my eyes.
Click to expand...
The track bar is the worst place for something to be really loose. There should be ZERO movement in those two bushings/ends. ZERO side-to-side, only rotational being normal.

The upper end is a tie rod end cast into the bar, and that is not a bushing but a rubber grease boot. But if it is cracked and the joint has play side-to-side then I would replace the track bar.

If this does need replacement it will need to be done ASAP or you will tear up everything that works with the track bar up front, which will cost you a lot more.

The upper track bar hole is tapered and it mounts up just like a TRE. This much vibration could have wallowed out that hole so that it can no longer be tightened down and provide the solidity it is supposed to give your ride.

When this happens, many of us opt for an aftermarket track bar, which will not have the cast-on TRE. Frequently with these you will have to drill out the hole in the frame bracket to accept a heim joint or some such.

One of the best of these based on clearance, fit and price is the one made by Metalcloak. I would take a look at one of those if you opt to not get a stock track bar.

Good luck!
 
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Apocalypticsurf6
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