New lift, funky symptoms. Need advice. UPDATE

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JT1

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You can't squash geometry.

The only practical way to retain scrub radius when lifting a Jeep and jamming big tires under it is to run a axle that is wide enough to allow you to place the tires in the right location for the SAI.

It's kinda a big deal if you don't want to learn how to drive a Jeep with mucked up geometry.
Not trying to squash it at all, but I don't think I've seen a chart or the breakdown with SAI's at 13ish degrees.
I can supply all the stats if I can find the formula for it..

And caster should affect the SAI also, right?
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Have you tried your old wheels and tires to see if it's still having these issues? If adjusting tire pressure is having an impact, the tires are probably junk.
 

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...caster should affect the SAI also, right?
You can look at it that way, but the Caster just changes the fore aft center of the contact patch. The SAI is the same regardless, and there fore the radius of the scrub is the same. If you keep adding caster you can make the steering feel sluggish which may mask the affect of scrub radius, but only by increasing opposition of forces, rather than by finding the sweet spot where the system works together with a minimum of effort.
 
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JT1

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Have you tried your old wheels and tires to see if it's still having these issues? If adjusting tire pressure is having an impact, the tires are probably junk.
Not sure what you mean? Overinflate your factory tires to 45# It'll drive like garbage too.
 

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Not trying to squash it at all, but I don't think I've seen a chart or the breakdown with SAI's at 13ish degrees.
I can supply all the stats if I can find the formula for it..

And caster should affect the SAI also, right?
I don't think so, Caster is forward to back rotation of the axle. SAI is the side-to-side angle between the tire and the steering, similar plane to Camber (which is tire to axle if I remember right). You're making me learn all this better, lol.

They still relate, but their impact is felt in scrub radius, not to one another. Changing Caster can change the impact of Camber and SAI on scrub radius. However, Caster doesn't actually change Camber or SAI, just the angles they all impact your tire's placement on the ground and it's orientation (Camber, Toe, Scrub Radius, etc).

Clear as mud?
Edit: I think this is why some suspension engineers and technicians hate our community, lol.
 
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JT1

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I don't think so, Caster is forward to back rotation of the axle. SAI is the side-to-side angle between the tire and the steering, similar plane to Camber (which is tire to axle if I remember right). You're making me learn all this better, lol.

They still relate, but their impact is felt in scrub radius, not to one another. Changing Caster can change the impact of Camber and SAI on scrub radius. However, Caster doesn't actually change Camber or SAI, just the angles they all impact your tire's placement on the ground and it's orientation (Camber, Toe, Scrub Radius, etc).

Clear as mud?
Edit: I think this is why some suspension engineers and technicians hate our community, lol.
100% As simple as these solid axles are, there are still some relationships in there that seem like voodoo.

Has anyone tried the steering module reset by chance?
 

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JT1

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Did the steering module reboot that was posted on here earlier, pull F34, start it, turn it off and then let it sit. Then restart, turn full left, then full right then center and turn it off..

Completely fixed the issue. Roads that were nearly impossible to drive are now normal, and the hunting for straight ahead is much better. Some quality highway time will give me a better chance to determine if that part is fixed, but the low speed stuff is resolved
 

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This pic just hurt my soul. I've been waiting on my ats for at least 3-3.5 months. 🤣🤣🤣
Yea, I keep extra Biscuit around for Roky Jelly. Just curious where did you order yours from?

Jelly Biscuit .jpg
 
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