Wheel shimmy

[Chuck]

New to this forum. I have a m38a1 /55 I drive every day on the Roads. Lately I've notice a shimmy sometimes after hitting a bump. ( steering wheel wabule). Steering is tight, ball joints good. Slight play in the bellcrank. Any ideas. Thanks.

[gmwillys]

Welcome Chuck!

The dreaded death wobble. I would go after the bell crank first, then go from there, since you have inspected the other prime players. If not, below is a pretty good thread that will give you some ideas.

https://forums.g503.com/viewtopic.php?t=20110

[bmorgil]

Hello Chuck!
Good link from gmwillys below. One of the easier things to check, and a common cause, are the wheel bearings getting loose. Just jack it up and check the play in the tire\wheel top to bottom. You should not feel very much. Very slight play top to bottom is all it will tolerate before it starts to shake. Running through the bell crank and, the link from gmwillys should find it. What ever you do, I would not put a steering stabilizer on it.

If you "ride" the brakes slightly, just drag the front shoes while you hold your speed, what does it do?

[Chuck]

Thxs for the help.

[Chuck]

Hello again. I wanted to mention. It does have a stablizer on the ty rods. Can this cause a problem if it old & not working properly?

[bmorgil]

Chuck, I think those who know about the way front suspension works, might agree with this. The "stabilizer" is really there to help with the large feedback to the steering wheel when off roading. The big hits to the wheels can transfer the abrupt motion to the wheel and jerk it in your hands. This was really the original intent. In doing so, the stabilizer does impart an extra load to the system. In manual steering it will increase the effort to turn when the steering wheel is turned quickly. They can mess with the steering wheel "return". They will not fix the wobble. They will only do a half attempt at hiding it. Used as intended they are mandatory if you are truly off roading it hard. In the rocks you would wish you had one. They look cool I guess. They work great in off road competition.

I would unbolt the stabilizer, and check the tie rods and all again for looseness. It could be making it difficult to detect looseness. I would check for looseness in all the components in the gmwillys link. If you do not have at least 12 to 16 lbs of smooth preload on the knuckle bearings without the seals, they are suspect.

I would not use a stabilizer on a CJ running on the street with little true off road bumping. The extra load messes with a lot of things. Without a doubt the best thing to do is find the cause. Set up correctly, the "Death Wobble" won't come calling.

[Chuck]

Thanks all. I'll get at it this weekend & go from there.

[gmwillys]

you'll never see an old Jeeper drive with their thumbs inside of the steering wheel. It is a true statement from bmorgil that the stabilizer is there to cushion and abrupt shock to the steering. It can reduce the amount of death wobble, but it is just a band aid often used to mask the problem.

[Chuck]

I pulled the bellcrank off. The needles fell out, the bearing surface was distorted from bearings not rolling. The ball on the end of the crank had some flat spots as well. I priced out parts from Texas at roughly $100 bucks. I'm guessing it was the original parts in it. Easy job best completed with the rad pulled. Thxs all it was fun.

[LarrBeard]

I pulled the bellcrank off. The needles fell out, the bearing surface was distorted from bearings not rolling. The ball on the end of the crank had some flat spots as well.

Hopefully that will be all that you find and the fix will be easy.

Post us a picture of the M38 ... .

[Chuck]

4466not sure if the pic will come thru.

[Chuck]

4467 i think this went thru.

[gmwillys]

Good looking Jeep!

[LarrBeard]

4467 i think this went thru.

Oh yeah - it went through. Very nice. It looks like it is a light grey - is it really "frost camouflage" or just color balance in the photo?

[Sebastian21]

The most likely cause, if the front end is tight, is the wrong shocks. I have had two four wheel drives that shimmied after hiting holes, and in both cases the cause was shocks not tuned to the suspension. There is no way for the home mechanic to figure this out so you have to go with the factory shocks. Amy brand is ok but must meet factory specifications not ones that just look right.

[Chuck]

I'm just waiting for parts right now. After I put it together & test it out if there's still a shimmy I will ck out the shocks. T hxs.

[Chuck]

Yea I think it's frost.