Steering wander and front axle movement

[koning2e]

Bought my first Jeep TJ recently and started noticing steering wander. I found all the other existing great threads about steering wander and how to perform the two tests: dry test and engine on test to see how the arms and track bars performs. What I noticed right away was that the front axle and the whole body of the jeep seemed to move left and right when turning the steering wheel left and right. When I looked closer, the upper control arms where moving sideways also. Would this indicate that these and perhaps the lower control arms need replacing? The steering wander is more profound when turning left. Adding some photos also.

 

[Jerry Bransford]

That your axle moves left/right in response to turning your steering wheel right/left indicates a problem with the track bar, perhaps the bushings in the track bar have worn out. The track bar is 100% responsible for keeping your axle held firmly and centered as your steering wheel is turned left/right.

The control arms would have nothing to do with that particular problem.

 

[koning2e]

Thanks Jerry. Makes sense. And that in turn would impact steering wander also I guess. I cannot do the work myself but will ask a local trusted car mechanic to take a look for me.

 

[Jerry Bransford]

Also have that local mechanic replace your dropped Pitman arm that I just noticed with the factory Pitman arm. WIth your track bar design, which does not utilize a dropped mount, you should be using the factory non-dropped Pitman arm. Your current dropped Pitman arm is causing bump steer which will force your steering left/right as your front axle moves up/down when you drive over bump/dips on the road.

 

[Mattific]

Your upper control arm (diff side) also appears to have a bent or misaligned bolt on the axle side from the pictures

 

[koning2e]

Thank Jerry. I wish I could buy you a few beers because you are always so helpful. Here is a better photo of the pitman arm.

 

[Jerry Bransford]

Try this too... with the tires on the ground, have a helper repeatedly turn the steering wheel in quick short left/right movements while you watch the track bar's two mounts. Find out which side's mount it is moving from to give you a better idea of what's happening.

P.S. Yes that's definitely a deeply dropped Pitman arm which shouldn't be there. Replace it with the factory OE Pitman arm.

 

[koning2e]

Your upper control arm (diff side) also appears to have a bent or misaligned bolt on the axle side from the pictures

Yes noticed that too. Thanks.

 

[koning2e]

Also have that local mechanic replace your dropped Pitman arm that I just noticed with the factory Pitman arm. WIth your track bar design, which does not utilize a dropped mount, you should be using the factory non-dropped Pitman arm.

Even with the Jeep having been lifted? I thought that perhaps they changed it due to the lift which is about 4 I think.

 

[Jerry Bransford]

Even with the Jeep having been lifted? I thought that perhaps they changed it due to the lift which is about 4 I think.

Even with the Jeep having been lifted. My TJ is lifted 4" and it's running the factory Pitman arm. My previous TJ had nearly 5.5" of lift and it was running the OE non-dropped Pitman arm. Very rarely should a dropped PItman arm be installed onto a TJ.

Older pre-TJ Jeep models like CJs and YJs usually needed dropped Pitman arms once a suspension lift was installed. The TJ's improved steering geometry eliminates the need for a dropped Pitman arm for most situations which generally include only when there's also a dropped track bar mount which your TJ does not have.

 

[LukesfirstJeep]

Your upper control arm (diff side) also appears to have a bent or misaligned bolt on the axle side from the pictures

I saw that also, but to me, it looked like the bolt diameter is much smaller than the ID of the control arm bushing. I was thinking the bushing is missing the inner metal sleeve.

 

[koning2e]

P.S. Yes that's definitely a deeply dropped Pitman arm which shouldn't be there. Replace it with the factory OE Pitman arm.

Hey Jerry, if I get the factory OE Pitman arm to replace the dropped arm, would I then also need to get a different drag link? The arm would sit higher meaning the angle to connect the drag link to the steering link by the wheel would seem wrong. Or am I wrong in assuming that? My mechanic also looked at the Pitman arm and during dry test we noticed play where the arm is attach. He tried to tighten the nut but it was super tight.

 

[BuildBreakRepeat]

Hey Jerry, if I get the factory OE Pitman arm to replace the dropped arm, would I then also need to get a different drag link? The arm would sit higher meaning the angle to connect the drag link to the steering link by the wheel would seem wrong. Or am I wrong in assuming that? My mechanic also looked at the Pitman arm and during dry test we noticed play where the arm is attach. He tried to tighten the nut but it was super tight.

View attachment 82043

You won’t need to get a longer drag link, the play your are seeing is from a worn tie rod end that should probably be replaced. The best course of action for your setup is the Currie Currectlync. It’s designed the correct the angles at 4” and seriously beef up the steering in general. At your lift height you don’t need to worry about the angle of your TRE, it will be totally fine. Unless you’re at 8+ inches of suspension lift a dropped pitman arm does way more hurt to the steering geometry than help, the only instance where this isn’t true is if you were to install a dropped track bar mount at the frame - which is a bad idea anyway and i can go into details why if you’re curious! Also, if you’re technically inclined, tie rod ends can handle some pretty significant deflection angles without worry - see the image below. The deflection at your lift height just isn’t enough to cause concern.

 

[koning2e]

You won’t need to get a longer drag link, the play your are seeing is from a worn tie rod end that should probably be replaced. The best course of action for your setup is the Currie Currectlync. It’s designed the correct the angles at 4” and seriously beef up the steering in general. At your lift height you don’t need to worry about the angle of your TRE, it will be totally fine. Unless you’re at 8+ inches of suspension lift a dropped pitman arm does way more hurt to the steering geometry than help, the only instance where this isn’t true is if you were to install a dropped track bar mount at the frame - which is a bad idea anyway and i can go into details why if you’re curious! Also, if you’re technically inclined, tie rod ends can handle some pretty significant deflection angles without worry - see the image below. The deflection at your lift height just isn’t enough to cause concern.

Thanks for the quick response. Forgive my novice ignorance, if the Pitman Arm end sits higher, would therefore the TRE not come to sit too low? See arrows in my photo.

 

[Mikester86]

Thanks for the quick response. Forgive my novice ignorance, if the Pitman Arm end sits higher, would therefore the TRE not come to sit too low? See arrows in my photo.

View attachment 82052

I had a dropped pitman arm and replaced it. I had to recenter the steering wheel after, which cannot get much simpler. That was all, it set the front geometry where it needs to be. Photo is after stock pitman arm install.

 

[BuildBreakRepeat]

Thanks for the quick response. Forgive my novice ignorance, if the Pitman Arm end sits higher, would therefore the TRE not come to sit too low? See arrows in my photo.

View attachment 82052

No it won’t be too low, the specific geometry that keeps the steering from being affected by driving around hitting bumps and curves is due to the relationship between the track bar and drag link - they need to be as close to parallel to each other and equal length as possible - keep in mind measuring from bolt hole to bolt hole not the actual bar. If you do this measurement you’ll see the drop pitman arm causes them to not be close to parallel as with a stock arm - meaning that as the suspension cycles over a bump or a curve the arc the axle moves in does not match the arc of the drag link and moves the wheel on its own. You want your components to be in sync and not fighting each other - with a stock track bar mount the pitman arm needs to be stock to keep the arc travel close and parallel.

You’re original question about how the entire Jeep moves when steering is due to those angles not being close - they are fighting each other and moving the body as a result - not a good situation.

 

[ChristopherD]

I really don't want to hijack someone's post but I feel like this group of guys have some good knowledge I need. I don't know the lift and its given me problem after problem since I bought the Jeep. I measured my springs and came up with the lift being 5". Do I need this pitman arm or a stock one?

 

[BuildBreakRepeat]

I really don't want to hijack someone's post but I feel like this group of guys have some good knowledge I need. I don't know the lift and its given me problem after problem since I bought the Jeep. I measured my springs and came up with the lift being 5". Do I need this pitman arm or a stock one?View attachment 82159

Are you experiencing bump steer? Like the steering wheel moves when traveling down the road and you hit a bump or pothole? 5” of lift is still within the parameters for a stock pitman arm since your trackbar is in the stock location. Keep in mind the steering wheel should stay perfectly straight with no movement over bumps.

 

[ChristopherD]

Are you experiencing bump steer? Like the steering wheel moves when traveling down the road and you hit a bump or pothole? 5” of lift is still within the parameters for a stock pitman arm since your trackbar is in the stock location. Keep in mind the steering wheel should stay perfectly straight with no movement over bumps.

Bumpsteer, wandering, death wobble, no return to center at all, etc. With the bumpsteer part the steering wheel doesn't turn but the Jeep is constantly going crazy and it's influenced by bumps and dips in the road. I drive a 18 year old, over weight, GMC 6500 for work and it's drives better than my Jeep does

 

[BuildBreakRepeat]

Bumpsteer, wandering, death wobble, no return to center at all, etc. With the bumpsteer part the steering wheel doesn't turn but the Jeep is constantly going crazy and it's influenced by bumps and dips in the road. I drive a 18 year old, over weight, GMC 6500 for work and it's drives better than my Jeep does

Not trying to take away from the OP’s thread but let me break it down for you for a second. Death wobble is due to loose components - primary being the track bar. If you have a buddy shimmy the steering wheel back and forth while in park and engine off you’ll be able to see what components have play. Bumpsteer is due to your dropped pitman arm and the inverted T steering your currently running instead of the OEM Jeep steering of inverted Y. Wandering/tracking/return to center are affect by three things, loose components (death wobble also a symptom), not enough caster, or not enough toe-in. Check the toe by measuring the front of your tires across and the rear of your tires across and comparing the numbers. There’s threads on here for setting toe. Check your caster/pinion angles with an angle finder pressed against the driveshaft and input yoke to the differential. Loose components can be checked by the method I laid out above with your buddy, or by visually inspecting bushing for cracking and/or play. Feel free to PM me if you want some help with your numbers!