Starting to track down a wobble/shimmy

[RedChili]

Wife had to drive the gladiator this morning to work, and while on the way she said the truck started "shaking a lot" and she said it felt like a wheel was about to fall off -- this was as she was driving about 45-45 mph. I swapped out cars with her and went on the same road at the same speed and did not get any type of wobble, but I need to start to troubleshoot to see what might be causing the issue. So I have a MC 3.5 Gamechanger lift, RPM 2.5 ton aluminum steering kit, With Fox 2.0 through stabilizer, ADS shocks in all four corners, Adam's driveshaft, Revolution re-gear (5.13), 17x12.5 method 315 Standard wheels (-12/4.5) and 38" Ridge Grapplers. The upgrades were done by a shop in Scottsdale this spring and I have about 3500 miles on since install. Truck is driven daily to and from work on road with some easy trails/washed-out dirt roads on the weekends. Tire pressure is set to 31. It has been cold the last couple of days with morning temps in the low teens so tire pressure sits at about 26-27 in the mornings. I have no issues with this setup so far, until this morning. I know this can be caused by a number of issues so I'm trying to trouble shoot some. Shop that did the work is about 5 hours away and I think I'll end up there or another shop eventually, but I'm trying to figure out some possible causes before making that trip...especially with a potentially dangerous "wobble/shimmy".

About three weeks ago I noticed a glob of grease on tie rod. I looked at the drag link and noticed the boot was covered in grease and that's where the glob apparently originated from.

I wiped up the grease and noticed that the boot has split (can sort of see it in the top left of the "clean" picture below):

My question is, does the angle look correct here? I'm not sure if the joint needs to be more parallel to each other and maybe that's why the boot split, or maybe the shop just filled it with too much grease? I have no idea if this might have been the cause or if it just looked off to my untrained eye?

Sponsored

 

[ShadowsPapa]

My question is, does the angle look correct here? I'm not sure if the joint needs to be more parallel to each other and maybe that's why the boot split, or maybe the shop just filled it with too much grease? I have no idea if this might have been the cause or if it just looked off to my untrained eye?

I'm not going to suggest a cause, but general rule of thumb I was taught in college alignment/front end/suspension classes - try to keep any joints even with each other. In other words, if one end of a tie rod has the end sitting perfectly level, the other end should be as well. Otherwise you potentially limit the travel - one will hit the side while the other has room to move.

Possible it was "over greased". We always greased to the point of an unsealed joint showing the old grease coming out, then wiped up, cleaned up the grease, and semi-sealed boots - not open on the bottom like the umbrella type shield - we greased until the boot started to swell and just barely started force grease out. This ensured new grease in, dirty grease pushed out. With extreme movement, heat, vibrations and so on, the grease can be forced out. Hard to really "over grease" because the idea is to get new, clean, good grease in and the old dirty out of the way. A good suspension guy will clean up the excess grease.

I'm bothered by this angle (pic below), but not being under and looking at both ends - looking only at this one, it seems to be rather severe.
If the other end is level and this one at this angle, that would bother me even more.
If both ends were angled like this, not so much, but still, if I draw a line down through the center of the tapered stud and down through the joint, this seems off.
I'm only offering things that "bugs me" and am not suggesting any cause. If it was my truck, I'd do more looking and digging around.
I'd look for play.

The grease could be the result of that joint being "hammered" by the extreme wobble. The the joint is being smashed back and forth, left and right, against the "stem" inside, forcing grease out.
Check for damage at that joint.

 

[Gizmo]

Do the Dry Steering test and look and feel for play in every connection

 

[RedChili]

Thank you for the responses! I’ll take a closer look at that joint and start to shake down other causes as well. The funny thing is I was just thinking to myself on Monday how nice the truck was handling…I must have jinxed it!

 

[ParatusExpeditions]

Any updates?

 

[RedChili]

Any updates?

Well, haha, I wish! So its a strange one, and likely way out of my wheel house to deal with alone, so I'm trying to get it into a shop to check the alignment and the steering components/suspension.

I did a dry steering test and could not detect any, what I'll call "lateral slop", that is any slop side to side with the tie rod and drag link. In other words I could not feel any slop in the tie rod joint or drag link with movement parallel to the ground between the wheels or side to side slop. I had my hands on the joints and they felt smooth while the components were turning back and forth. During the dry steering test there doesn't seem to be any movement inside the joints but there is small noise that seems to indicate some extra movement but its hard to tell if its from the ball joints or tie rod joint or where. If there is any slop in there its minimal. There's no loud "clunk" or jarring movements that seem to be off so I guess that's good?

However, if I grab the tie rod, for example and pull up or push down perpendicular to the ground, there's a lot of movement. maybe an inch or more. The joint itself doesn't move but the bar moves. I have no idea if this is normal or abnormal? I know the joints must have some up and down movement, but it seems to be pretty lose, but again, I have no frame of reference to know how much up and down movement it should have if any.

Changed the tire pressure some to see if that would help or harm. Before the wobble began I put my tire pressure down to 30psi (cold pressure) and the truck seemed to run great for a couple of weeks, just prior to the wobble appearing. It has been cold so the morning pressures where showing 27-28 psi. So I added some air (33psi) to see if that would make a difference and it seemed to help, but I would still feel a shimmy after hitting a small bump (manhole cover for example) above 40 mph. I added some more air (36psi) and this morning got a bad wobble at 35mph on a manhole cover (my drive to work goes over lots of manhole covers) so that definitely made it worse.

I cant tell if anything has come loose or moved because there are no torque markings. I wish the shop had done that so I could at least tell if anything had moved, but oh well.

So that's where I am. Should get into a shop to check the alignment and suspension components this week, so hopefully I can get some more answers then.

 

[AmosMoses]

Iam in the same boat as you I think. Bought a used 2021 jtr this spring and now that temps are going down I've been noticing some shimmy in the front end when going over bumpy roads. Only thing I've added is 35x10.5 wheels from my old sport I sold. I haven't had time to mess with it yet as Iam working alot of overtime right now but will be watching this thread. I need to get out and check torque on everything under there.

 

[RedChili]

Got it into a shop late this afternoon and so hopefully there will be some headway soon. I did notice that quite a bit of grease seemed to have come from the joints on the front tie rod and drag link both (picture in the beginning of the thread were just of one joint on the drag link) so maybe that's the potential source? I told the mechanic about the odd shape of the joint angle (from above) and the other greasy joints as well, but he said he'll check all of the possible sources. He seems very knowledgeable and my father-in-law (an "old" jeep guy) recommended him and says he knows his stuff, so I'm hopefully optimistic. I'll update again once I get more info which may hopefully help someone else!

 

[AmosMoses]

I just checked my lower ball joint nuts and they were tight. My drag link joint that connects to the pitman arm is not canted like yours though. It is parallel to the pitman arm joint. Hopefully your shop figures something out for you.

 

[RedChili]

I just checked my lower ball joint nuts and they were tight. My drag link joint that connects to the pitman arm is not canted like yours though. It is parallel to the pitman arm joint. Hopefully your shop figures something out for you.

That's good info, thank you! I'm thinking that's where my issue will end up being, at least partially. I'll for sure get an update once I hear something. Hope your gets figured out as well!

 

[ParatusExpeditions]

So im also chasing similar. Also did a dry check, nothing. However I see a few ball joints that do hop a bit / bind at the pitman arm location, see:

I can also wiggle my drag link and tire rod a bit:

Now, I’ve asked friends to try on theirs and it’s solid no play at all. They’re also not sending it like monkeys ont the trail like I do sometimes, so there is that.

Ah, and my steering stabilizer (OEM) is slightly bent and leaking, in other words dead. But mostly hiding would only hide the issue if it was working fine.

I should also note that I’ve re torqued lower and upper control arms, that I have paint on ball joints nuts and what in and nothing moved. Still reproduces, so I’m fairly confident the ball joints took a hit from my driving and added weight. I plan on running stronger steering and stronger ball joint if Black Friday deals are nice. Ive also checked tire balancing and rotation, still nothing. What I haven’t done is alignment.

 

[ParatusExpeditions]

What bugs me is that I’m also aiming for RPM or alike and I don’t like the way those boots and angle look on your install. Have you checked at install time if that angle was already like this?

Feels like this shouldn’t happen in normal condition and it is an error made at install time?

EDIT: I’ve also found this from their social so angle may be fine:

 

[RedChili]

Just a quick update with out a lot of good info...Took it to a shop recommended by an in-law and the good news is the wobble is gone, the bad news is I'm not sure how the shop did it, other than make adjustments to the alignment. Not sure if it was castor, camber or what as I still need to talk to mechanic directly. He just said the alignment was off several degrees and he had to make some adjustments to the drive shaft and axle position but no worn out joints or anything like that. He also re-balanced the tires/wheels for good measure. I'll try and track down some specifics, just in case in might help anyone else experiencing the same, and post a final follow up. I am also likely going to take it out of town to another shop, just to get it triple checked and I may end up getting a PSC kit thrown on for good measure.

 

[ShadowsPapa]

He just said the alignment was off several degrees and he had to make some adjustments to the drive shaft and axle position but no worn out joints or anything like that.

"Several degrees" indicates actual damage. Not just "adjustment out of whack". You don't get anything out "several degrees" without something being bent or damaged or otherwise shot.
You don't adjust for "several degrees". Maybe a degree or two - but several?
Adjustments to the driveshaft? That's nothing to do with wobble.
Almost sounds like he made massive changes to caster and had to turn the pinion back into alignment (axle position). To go that far would require parts - like adjustable control arms, etc.

Yeah, you'd better find out what he did!

 

[RedChili]

"Several degrees" indicates actual damage. Not just "adjustment out of whack". You don't get anything out "several degrees" without something being bent or damaged or otherwise shot.
You don't adjust for "several degrees". Maybe a degree or two - but several?
Adjustments to the driveshaft? That's nothing to do with wobble.
Almost sounds like he made massive changes to caster and had to turn the pinion back into alignment (axle position). To go that far would require parts - like adjustable control arms, etc.

Yeah, you'd better find out what he did!

Well shoot. That's not good. Thank you for the heads up!

Sponsored