[SeaComms]

My daughter had a wobble start in her 07 Wrangler,stock jeep.Got burned by Firestone and the steering damper sale.Brought to me (30 year front end mechanic on cars to semi's).I put it on the alignment rack,lowered the caster from 7.0 degrees to 4.8 degrees,wobble gone.Of course I checked thr front end out and everything was tight.Jeep drives great and no wobble.I have written on other places in this forum and had others try the caster change after checking all the front end parts out.it does work if you can find a front end man that will think out of the box and try it.

How did you adjust/lower the caster in a stock jeep? And how on earth did a stock Jeep get to 7 degrees? 4.8 is still higher than the stock range (3.7 to 4.7)

 

[SeaComms]

I am not doubting your knowledge, its just that you stated your daugters vehicle was a stock 2007 Wrangler. The 2007 JK doesnt have adjustable caster and specs are between 3.7 to 4.7 degrees (is there a 2007 TJ perhaps?).

Maybe Mitchel On Line is incorrect? Wouldnt be the first time, I stopped using them years ago due to wrong info.

 

[SeaComms]

Dana changed the paint on the diffs suplied to Jeep and its a thicker paint (much thicker than the water thin stuff it used to be). Basically when looking for a front end clunk a mechanic found the bolts to the diff were loosing torque as the paint was squashing under the bolts. He looked at several other vehicles and found the same thing.

Due to this, JKs made after mid 2010 with these "new paint" diffs are being recalled and all bolts on the diff (upper and lower control arms, track bar, ball joints etc) are being retorqued for safety reasons.

 

[SeaComms]

Yeah, the cams were one option I was looking at to increase the caster, as the lift has reduced mine to around 3.6 degrees and with no adjustments I find the steering very light and not self centering as much as I would like. The cams will give around another degree max, which is about all I need.

However, no one down here will sell the cams due to to many failures. I guess the problem is on a lifted Jeep they are more likely to be off roaders and heavy offroad work slamming the front wheels into things they say they will move (since the axle is pushed forward and its only the torque of the bolt and the washer agains the notch to hold it in place). And more than likely the nut behind the wheel not checking torques regularly...

Personally I am still not totally against the idea, as I do have a welder to lock them in place But its not urgent at the moment and I may still look at higher clearance adjustable lower control arms for that extra degree or so.

 

[SeaComms]

Lol, yeah, I have seen the knock outs and been contemplating it. There is a kit I saw somwhere that were simply square washers wide enough to fill the gap completely between the raised sections with the hole offset to max caster using the standard bolts. Contemplating this as could easily weld them in place to make it permanent so they dont move.

Have had a few guys down here say under the heavy load of hitting an obstacal pushes the diff back hard enough to push the washers past the tabs that stick out.

Personally I think if torqued properly this is highly unlikely, however as I mentioned a quick swipe with the welder and this problem should be solved

 

[SeaComms]

....and there is a TSB about re-torquing the suspension bolts for a limited number of one year model JK jeeps...

Yeah that was a good one!

Apparently Dana changed the paint from the traditional thin (watery looking, barely coating, let rust show through while still on the showroom floor) diff paint to a luscious thick more vinyl looking paint.

Chrysler did up all the suspension components to correct torque settings at the factory, only to find as the diffs heat up from usage, they soften this new nice thick good looking paint and the bolts are all no longer tight enough :banghead:

 

[SeaComms]

What lift do you have in it, and what if any changes have been made to the caster settings?

I have just gone through this myself, with what first showed up when hitting bumps at highway speeds, though not all bumps only some, the steering wheel would wobble then slowly over a few seconds reduce back to still again. This happened for a few weeks, then one day it just didnt stop after I hit a small pothole and I had to slow from 110km/hr (70mph) to below 80km/hr (50mph) before the wobble would stop.

I went over everything with a fine tooth comb and there was no movement or freeplay in any components at all. What I did find was my caster was down to about 3.6 degrees after the lift (currently sitting at about 2.75in on the front and 3in on the rear).

After much research I have diagnosed my issue as a caster wobble. Or to be more exact, a lack of caster wobble. Think of pushing a shopping trolley along and suddenly one of the wheels starts wobbling like crazy - thats a caster wobble.

You need around 4.5 degrees or higher to be stable. Mine is now sitting at 5.3 degrees, prob a little higher than it needs to be, but I jsut fitted the AEV front control arm drop brackets that are not recommended for below 3.5in lift. Still, very happy with the ride and the wobble is history.

 

[SeaComms]

The only adjustment required will be the draglink length to recentre the steering wheel.

Before dropping the springs out though, make sure he loosens all control arm and track bolts to allow the bushes to move on the bolts and not twist around themselves.

Once new spacers are in, drop it onto its wheels so the full body weight is on the suspension before doing all the control arm and track bar bolts back up. While he's at it I would recommend twisting the top of the front diff as far back as the slop in the bolts will allow before doing them up to make sure the maximum possible caster is achieved.

Thats it!

 

[SeaComms]

Question: While doing my typical look over under the hood, I reached down and gave an up/down tug on the tie rod, drag link, and the track bar.

While the track bar is immovable, both the tie rod and the drag link can be readily moved up and down by hand. Is this normal?

Depends what you mean by up and down movement. As the bars are not straight, 'lifting' will make it rotate (and quite easily), this is normal.

If you can make the rod end move up and down then the rod ends are stuffed.

 

[SeaComms]

Just installed a 3.25" lift on my 2011 wrangler 4 door JK and seemed fine until I hit a pothole doing about 65 MPH (Speed limit was 70 MPH) and the front end felt like the whole world was about to end. It was the death wobble as described. I have been offroading and installing my own lift kits for over thirty years with no problems. I can't believe that a few lines of instruction about loosening my front track bar and re torquing after installed were not included. This is some pretty important info and thank goodness this forum is here. Thanks for the technical info. it may just have saved my jeep or even my life!!
jkclyde

What caster correcting gear was used in the lift? Have you had the caster checked since installing the lift? What wheels/tyres and offset do you have?

 

[SeaComms]

With an answer like that I would definitely be looking at your own tools or a local club!

But then its not an unexpected answer, we get the same blank stare from dealers down here when asking them the same question.

It could be that a lot actually know what you are talking about, but a little thing called deniability creeps in and creates the blank response....

 

[SeaComms]

Any idea why i still have a slight shimmy? Only if i hit a nice size bump.

Yeah, its to do with the large heavy wheels and movement in the trackbar and control arm bushes. A heavier duty steering damper may reduce the shimmy over bumps, as probably would heavier duty (more solid) bushes for all suspension joints, and as would lighter wheels (smaller).

Its all a compromise, as stiffer bushes will increase ride harshness over small bumps and a heavier damper will make for heavier steering (though thats prob not a bad thing for most JK's), and smaller lighter wheels?? not likely!

Once thing I havent seen mentioned is what lift you have and what your caster angle is - lower caster will increase the tendancy to shimmy over small bumps as well.

 

[SeaComms]

Drop pitman arm cant be used on its own, it can only be used in conjunction with a track bar lift bracket to keep the drag link and track bar parallel to each other, other wise as you have found bump steer increases dramatically.

Sounds like you have the stock control arms and not yet fitted cam bolts (which is a good thing). In this case you have around 3.5 degrees of caster - not enough.

Two options then at this point, not including cam bolts as I dont like them Fit adjustable upper or lower or both control arms, or, as I recently did, fit the AEV control arm drop brackets. The brackets are quick and easy to fit, cheap in comparison to new control arms and also retain the stock bushes which are pretty damn good. Downside is they drop the rear of the lower control arm about 2in, only a problem if you are a rock crawler though.

 

[SeaComms]

LOL. Love it when you have to resort to printing out information from a forum to give to the "professionals" so they can attempt to fix something.

 

[SeaComms]

Dont know about over there, but down here I need to go to a specialist nut and bolt supplier to get them in that size at grade 8.

Though I do remember seeing on one of the 4wd places web sites a kit that replaced a lot of the bolts with the ones correctly fitting the holes! Beats me why they would do it in the first place. I mean if you are going to drill imperial holes, fit imperial bolts.

I believe they should be a fine pitch thread as per the stock ones (18 TPI from memory), not a coarse thread (12 TPI from memory), however I did noticed that AEV used the coarse thread ones in their kits.

Tests performed by Ajax Fasteners showed that the fine pitch threads are less prone to loosening from vibration:

Conclusion:
The suitability of a coarse or fine thread for a particular application has to be determined on a
case by case basis. In general, both coarse and fine threads are capable of providing sufficient
strength for most applications. Coarse threads are easier to assemble and need less care; hence
they are more commonly used. Fine threads will, in general, have higher load carrying
capacities and higher resistance to vibration loosening. Fine threads are less tolerant to damage
and are easily cross-threaded and therefore require careful assembly.

 

[SeaComms]

Yeah, same deal. Some of the guys down here were organising with one of the local nut/bolt suppliers to put together their own kit for all track bar and control arm bolts as none of them are the right size.

The only strange one we have is the steering damper we get is 12mm sleeves, so when I stuck on the Poly Performance damper relocation kit including the alloy clamp for the tie rod, the new bolts wouldn't fit through our stock damper as they were 1/2 in. Fortunately I had removed the unneeded sleeves from the PP sway bar links (as I fitted the disconnect kit too) so was able to push out the old 12mm ones and replace with the spare 1/2in ones.

 

[SeaComms]

For some reason they are only listed as 75 ft lb.

 

[SeaComms]

Oh bugger, apologies - I just reread the previous post and somehow did not see the lower arm part of the post! I though rome215 was asking for the uppers only....

 

[SeaComms]

That steering stabiliser being fitted is the same as the one fitted down here as a TSB in early 2010.

Personally I dont think its much different, just looks a lot bigger as it has a plastic sleeve over the normally open end.

 

[SeaComms]

On the contrary, it does quite a bit, but what it does is what it says it does. It dampens the steering. If you hit a nice big rock off road with the outer edge of the wheel without it the wheel will jerk to the side pretty hard. This is what its designed to stop or reduce, and as correctly stated, its not designed to stop death wobbles. It will however mask it a little since it is supposed to stop sudden jerks to the side of the steering.

With the stock wheel offset being quite close to the steering knuckles there is not a lot of load on the damper, so it wont be or shouldnt be very obvious without one. stick 3in backspace wheels on and now you have some serious leverage when hitting a rock with one wheel and will prob need a heavy duty damper to stop the wheel pulling out of your hands.