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Another JL with swaying on highway speed with lift

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parkhs0316

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thank you so much I will give it a try
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first try dropping the tire pressure to 30 psi or just under that

if you have not done so get an alignment done at a good off road shop that does lifts, they will know how to tweak it rather than shoot for what the computer calls perfect

check torque on every bolt touched during the lift install if you have not already, they can loosen up over time even if properly installed
 

Djhyper66

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When my car drives funny I check all my lug nuts .. unscrew them and re-tighten .. and problem solved .. least for me !!
 

Arterius2

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Regarding tire pressure:

With a set of properly balanced tires and correct suspension geometer, you SHOULD NOT NEED to drop tire pressure down to 30 or even 15 as some suggested here. That is ridiculous. That isn't fixing the problem, that is just masking it and sweep it under the rug.

On my Duratracs (Load Range E) I have mine set to 36 psi as per instruction on door jam and mine tracks like a dream.
 

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Regarding tire pressure:

With a set of properly balanced tires and correct suspension geometer, you SHOULD NOT NEED to drop tire pressure down to 30 or even 15 as some suggested here. That is ridiculous. That isn't fixing the problem, that is just masking it and sweep it under the rug.

On my Duratracs (Load Range E) I have mine set to 36 psi as per instruction on door jam and mine tracks like a dream.
30psi is fine to drive on.... the suggested 15psi was for test purposes not to keep it that way.
 

Headbarcode

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I'd definitely lower the tire pressure to 30psi, as a starting point. Also, it's very possible that the alignment shop went with factory caster specs which are too low. Each one of those issues alone would cause steering wander. Both at the same time,....
 

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Regarding tire pressure:

With a set of properly balanced tires and correct suspension geometer, you SHOULD NOT NEED to drop tire pressure down to 30 or even 15 as some suggested here. That is ridiculous. That isn't fixing the problem, that is just masking it and sweep it under the rug.

On my Duratracs (Load Range E) I have mine set to 36 psi as per instruction on door jam and mine tracks like a dream.
Not to argue, but the instructions on the door are for stock tires period. The tracking is likely caster, the firm ride on the other hand is 100% affected by the tire pressure. I'm sure potholes feel great with load range E tires at 36 psi, but I'll pass. There's a reason why things like the chalk test exist. If your tires are not stock, or at least close to stock, the door placard is useless. I don't think the 15psi comment was meant for daily driving, but rather as a quick test to see if the firm ride is caused by the spring/shock combo. The contact patch is better on our 37's at ~28-30 psi and the ride is so much nicer on our shitty California roads. After 15k miles our tires are wearing evenly across the contact patch, reaffirming our psi is correct for our rig. Tire inflation is not one size fits all.
 

Arterius2

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30psi is fine to drive on.... the suggested 15psi was for test purposes not to keep it that way.
Yes, 30 psi is 'fine' to drive on. But I definetly do notice that when driving on mine at 30 psi, my tires feel 'sticky' and sluggish at speeds.
 

Arterius2

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Not to argue, but the instructions on the door are for stock tires period. The tracking is likely caster, the firm ride on the other hand is 100% affected by the tire pressure. I'm sure potholes feel great with load range E tires at 36 psi, but I'll pass. There's a reason why things like the chalk test exist. If your tires are not stock, or at least close to stock, the door placard is useless. I don't think the 15psi comment was meant for daily driving, but rather as a quick test to see if the firm ride is caused by the spring/shock combo. The contact patch is better on our 37's at ~28-30 psi and the ride is so much nicer on our shitty California roads. After 15k miles our tires are wearing evenly across the contact patch, reaffirming our psi is correct for our rig. Tire inflation is not one size fits all.
I debunked the chalk-test myth a long time ago here.
The old chalk-test does not work on modern tires, unless you know exactly what to look for.

Modern AT/MT tires are designed so the outer lugs are not supposed to make full contact on flat pavement during normal driving, so if you go by the chalk-test you will always under-inflate your tires and introduce unnecessary wear, more road noise and decrease fuel mileage. The outer treads only comes in play to provide extra traction when you are off-road on uneven surfaces. This new concept is why modern AT/MT tires have jumped in fuel efficiency in recent years.

Yes, 36 psi might be on the slightly high side if you are on Load Range E tires, but honestly, with a properly balanced tires and alignment you should not be wandering even at 36psi. I've made many tests at different PSI on my tires and I find 36 psi to be comfortable and tracks straight and provides good fuel efficiency during my weekday city driving. I obviously do air down when I hit the trails.

Jeep Wrangler JL Another JL with swaying on highway speed with lift 1619202329143


If you looked at the tread pattern of the Duratrac tires you would immediately see why it's designed this way. The central treads are flat and are designed to make full contact on pavement during road driving. The inner lugs are oriented vertically and more densely packed so they provide less rolling resistance when driving on roads. The outer lugs are NOT designed to make full contact on roads when properly inflated so they are tapered out, they are horizontally and sparsely place apart to aid traction on rocks and mud. Obviously, when you air down on the trails, all lugs are making contact. Hope this helps.

Jeep Wrangler JL Another JL with swaying on highway speed with lift wrangler_duratrac_white_white_top3
 
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parkhs0316

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I dropped tire pressure to 30psi.. I will test is later today, but you guys could be right.. ALignment was done per factory spec.. and this could be the reason..

the only thing I hate about lower tire pressure is TPMS warning light on the dash.. I can't justify spending 300 plus to buy tazer to get rid of it
 

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I debunked the chalk-test myth a long time ago here.
The old chalk-test does not work on modern tires, unless you know exactly what to look for.

Modern agressive AT/MT tires are designed so the outer lugs are not supposed to make contact on flat pavement during normal driving, so if you go by the chalk-test you will always under-inflate your tires and introduce unnecessary wear, more road noise and decrease fuel mileage. The outer treads only comes in play to provide extra traction when you are off-road on uneven surfaces. This new concept is why modern AT/MT tires have jumped in fuel efficiency in recent years.

Yes, 36 psi might be on the slightly high side if you are on Load Range E tires, but honestly, with a properly balanced tires and alignment you should not be wandering even at 36psi. I've made many tests at different PSI on my tires and I find 36 psi to be comfortable and tracks straight and provides good fuel efficiency during my weekday city driving. I obviously do air down when I hit the trails.

1619202329143.png


If you looked at the tread pattern of the Duratrac tires you would immediately see why it's designed this way. The central treads are flat and are designed to make full contact on pavement during road driving. The inner lugs are oriented vertically and more densely packed so they provide less rolling resistance when driving on roads. The outer lugs are NOT designed to make contact on roads so they are tapered out, they are horizontally and sparely place apart to aid traction on rocks and mud. Hope this helps.

wrangler_duratrac_white_white_top3.jpg
I should have been more specific, my tires are not designed to run on the center lugs, and both wear and ride like shit over inflated. Correct, some tires are designed to not ride on the outer blocks.
Jeep Wrangler JL Another JL with swaying on highway speed with lift Screenshot_20210423-120312_Chrome
 
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Roky

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I dropped tire pressure to 30psi.. I will test is later today, but you guys could be right.. ALignment was done per factory spec.. and this could be the reason..

the only thing I hate about lower tire pressure is TPMS warning light on the dash.. I can't justify spending 300 plus to buy tazer to get rid of it
My recommendation would also be lower tire pressure to 30 warmed up and increase your caster, if it’s in spec then it’s to low. You’re on a lifted Jeep now, tire pressure specs and caster spec is out the window, you’re on a new “ within specs” category now. Als you have falcon stabilizer, probably has soft medium and firm. With increased caster 6 or more you don’t wanna run on the firm setting, it will counteract caster. Medium might as well , you’ll have to see what feels best.
 

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the only thing I hate about lower tire pressure is TPMS warning light on the dash.. I can't justify spending 300 plus to buy tazer to get rid of it
Tazers are great, but you could easily do that change with a few other software based tools for a fraction of the price.
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