Do I need an adjustable track bar?

The BAD Influence

The BAD Influence

Active Member
Please ignore the RC dual SS. I put that on prior to joining this site.

A few weeks ago I removed the relocation brackets and installed adjustable CAs. I've always noticed the front tires sat over to the passenger side too far. While finishing up the CAs I took the time to actually measure how far off the front axle was. It was 3/4 inch off.
A couple weeks ago I tried to adjust where the track bar attaches to the bracket. (Stock, non-adjustable track bar. The Rubicon express kit came with a track bar relocation bracket and drag link flip). There's only four adjustments that can be made; up, down, left or right. By adjusting the attachment location, it pulled the axle to perfect center. However, since that time (I did adjust the CAs and draglink after making the track bar adjustment. 4° and bottom lengths are both equal, top as well) it feels like at any moment we're going to go into death wobble. Between 40-50 mph the feeling is the worst, but at almost any speed, a bump will really get my heart racing. Based on what I'm seeing, the drag link and track bar are not exactly parallel. Given that I can only adjust the track bar at the attachment point, I'm wondering if I installed an adjustable track bar and then attached it higher if this would fix my problem.
Thank you for any ideas or suggestions.
IMG_20171025_164954664.jpgIMG_20171025_164942583.jpg

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krdadlamb said:
Please ignore the RC dual SS. I put that on prior to joining this site.

A few weeks ago I removed the relocation brackets and installed adjustable CAs. I've always noticed the front tires sat over to the passenger side too far. While finishing up the CAs I took the time to actually measure how far off the front axle was. It was 3/4 inch off.
A couple weeks ago I tried to adjust where the track bar attaches to the bracket. (Stock, non-adjustable track bar. The Rubicon express kit came with a track bar relocation bracket and drag link flip). There's only four adjustments that can be made; up, down, left or right. By adjusting the attachment location, it pulled the axle to perfect center. However, since that time (I did adjust the CAs and draglink after making the track bar adjustment. 4° and bottom lengths are both equal, top as well) it feels like at any moment we're going to go into death wobble. Between 40-50 mph the feeling is the worst, but at almost any speed, a bump will really get my heart racing. Based on what I'm seeing, the drag link and track bar are not exactly parallel. Given that I can only adjust the track bar at the attachment point, I'm wondering if I installed an adjustable track bar and then attached it higher if this would fix my problem.
Thank you for any ideas or suggestions.
View attachment 280897View attachment 280898

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Click to expand...

Trackbar and Draglink look parallel enough to me. Even if it wasn't it wouldn't cause death wobble - just bump steer.
Sounds like your dual stabilizers masked worn out parts - probably ball joints - that you are noticing more now.
 
JKDream said:
Trackbar and Draglink look parallel enough to me. Even if it wasn't it wouldn't cause death wobble - just bump steer.
Sounds like your dual stabilizers masked worn out parts - probably ball joints - that you are noticing more now.
Click to expand...
That makes sense. Bump steer sounds more like what I'm experiencing. Thank you.
Just checked the ball joints, there is absolutely no play in the tires, up and down or side to side.
The rubber on the tie rod end at the Pitman arm is broken. Maybe that joint is causing the problem.

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Ensure that track bar bolts are torqued to 125 ft lbs. And make sure there is no play there when someone turns the steering wheel back and forth.
 
As mentioned, have someone move the steering wheel back and forth and look for any loose movement in joints.

What's your castor? If it's only 4 degrees, you can dial in 5-6 to see how it drives. I'm running 7 degrees and it goes down the highway like a modern SUV at 70+mph. You have to watch for front drive shaft vibes if you crank up the castor too much with a taller lift. I'm only sitting at 3" so it works for me.
 
zimm said:
As mentioned, have someone move the steering wheel back and forth and look for any loose movement in joints.

What's your castor? If it's only 4 degrees, you can dial in 5-6 to see how it drives. I'm running 7 degrees and it goes down the highway like a modern SUV at 70+mph. You have to watch for front drive shaft vibes if you crank up the castor too much with a taller lift. I'm only sitting at 3" so it works for me.
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Thank you. I'm a newbie, so I didn't think to keep information regarding the lift. The kit came as a 3.5, but was clearly more. With the heavy bumpers and winch it's settled, but again no original numbers for a baseline.


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krdadlamb said:
Thank you. I'm a newbie, so I didn't think to keep information regarding the lift. The kit came as a 3.5, but was clearly more. With the heavy bumpers and winch it's settled, but again no original numbers for a baseline.


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Click to expand...

Please read this: https://project-jk.com/jeep-jk-tech...o-i-measure-it-and-how-does-it-affect-my-jeep

We need to know your castor to help diagnose. That's what the adjustable lower control arms are for.
 
Went to discount and had tires rotated and balanced. Then to Firestone to check the alignment. Castor angle is at 2.6. They wouldn't adjust the CAs nor let me do it in their shop. They did check ball joints and all other tie rods, everything was good.
 
krdadlamb said:
Went to discount and had tires rotated and balanced. Then to Firestone to check the alignment. Castor angle is at 2.6. They wouldn't adjust the CAs nor let me do it in their shop. They did check ball joints and all other tie rods, everything was good.
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Great! Lengthen the lowers to get 5degrees and problem should solved. You can use an angle finder on of of upper ball joint to mean sure castor. Verify your phone shows 2.6 and go to 5.
 
zimm said:
Great! Lengthen the lowers to get 5degrees and problem should solved. You can use an angle finder on of of upper ball joint to mean sure castor. Verify your phone shows 2.6 and go to 5.
Click to expand...

5 is pretty high for a stock housing. You'd be hard pressed to get there without causing other issues.
I'd aim for 3.5-4 to be honest.
 
Thanks guys. So lengthen the lowers or shorten the uppers? I know either will get me to a 4ish castor angle. I guess I always thought of lengthening the lower as pushing the axle further forward. Given that I've always worried about pushing it out of center I kinda thought of this as a last resort. But the EVO kit only comes with adjustable lowers, I'll concede to them that they know more than I do. Anyway, my question, is it "better" to shorten the uppers or lengthen the lowers?
 
krdadlamb said:
Thanks guys. So lengthen the lowers or shorten the uppers? I know either will get me to a 4ish castor angle. I guess I always thought of lengthening the lower as pushing the axle further forward. Given that I've always worried about pushing it out of center I kinda thought of this as a last resort. But the EVO kit only comes with adjustable lowers, I'll concede to them that they know more than I do. Anyway, my question, is it "better" to shorten the uppers or lengthen the lowers?
Click to expand...

Personally I would make the uppers stock length, lengthen the lowers then make sure your bump stops still line up


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Uppers are stock length. Castor is just above 6°, but my floor is just over 1°. Seems to ride significantly better. Thanks again for the help.
 
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