Changing parts to reduce wheel shimmy
After a recent tire rotation, I noticed that the steering had a small shake. Over time that shake got worse and worse. Then one day, I hit a bump, and there it was full-on Death Wobble.
I immediately ordered a track bar. https://amzn.to/2YTnvPT Because almost every Jeep that has come through my shop with death wobble, the problem was the track bar.
When I unbolted the axle end, I thought I had found the problem. The mounting hole was oval-shaped. I welded a washer over the hole and drilled it out to tightly fit the mounting bolt. A test drive showed this was not the problem.
So I went ahead and installed the new track bar. I had to use a tie road end breaker to get the tapered pin out of the mount as it had been in there a while.
A test drive showed the steering felt much better but there was still some shimmy at 55 to 60 MPH. I hit my test bump nad is was back to death wobble. But there was some improvement.
I had my Dad watch the steering while I worked the steering wheel and he noticed some play in one of the tie rod ends. So I ordered those.
Moog ES3095R Tie Rod End
Curiously, when I had my toe rod off the Jeep, I noticed that is was installed backwards. When I reinstalled it, I swapped the tie rod end for end and that makes the grease serts easier to access and now it matched the factory manual.
I did not take time to reset the toe but I counted the threads on the old tie rod ends and put the new ones in the same number of threads. A test drive showed the shimmy was gone and the feel was the steering was better. But the steering wheel was at an odd angle when straight. So I knew the alignment was probably off.
The next day I got out the Longacre alignment boards that I use on the race car and set them up. Sure enough he toe was way off. I dialed it in to near zero toe. A test drive showed the steering wheel was back to straight but the shimmy was not gone either. The test bump shoed still some wobble but it went away much faster.
Click image to open expanded view
There are still two tie rod ends that I can change. The control arm bushings are relatively new so I don’t think they are causing trouble. And I refuse to try the steering stabilizer as that only masks the real problem.
So I got to thinking about how the shimmy started after the tire rotation. I removed the front tires and rechecked the balance. They were both at Zero grams. So I decided to try swapping sides with the tires to spin them in the opposite direction.
So far, the shimmy is gone and there was no sake on the test bump. Could it have been simply the tires all along?