My Caster numbers, advice please.

Hale2016

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I have a 2021 Rubicon Unlimited and I installed the Mopar lift kit which gained me 2.75'' of lift. The Jeep drove decent with this lift as is but from researching I decided to add adjustable lower control arms. I purchased the Clayton Overland Plus LCA and set them to 24.5'' and now the Jeep seems to wander more and the wife is not happy since it's her daily driver. I'm thinking that I may have the LCA set too long based off of a cheap digital level that I have. Let me stress again this is a cheap digital level so I don't know how accurate it really is. I took the following measurements and got these results.

Top ball joint 8 degrees
Bottom ball joint 9 degrees
Flats on rear end housing 0 degrees

My level sit better on the bottom ball joint so I think that's the difference in the top and bottom readings. From everything I've read the caster should be between 5.5 - 6.5 for the best on road driving. I have an appointment to get it aligned next Monday so should I leave it until I have real numbers or shorten the LCA just a little? Could it also be the toe in after lifting that's causing it to drive a litte different?
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rkwfxd

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If I were having it professionally aligned on Monday I would not worry about it.

But it’s not my wife’s DD.

How ling were the arms you removed?
 

hoag4147

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I have a 2021 Rubicon Unlimited and I installed the Mopar lift kit which gained me 2.75'' of lift. The Jeep drove decent with this lift as is but from researching I decided to add adjustable lower control arms. I purchased the Clayton Overland Plus LCA and set them to 24.5'' and now the Jeep seems to wander more and the wife is not happy since it's her daily driver. I'm thinking that I may have the LCA set too long based off of a cheap digital level that I have. Let me stress again this is a cheap digital level so I don't know how accurate it really is. I took the following measurements and got these results.

Top ball joint 8 degrees
Bottom ball joint 9 degrees
Flats on rear end housing 0 degrees

My level sit better on the bottom ball joint so I think that's the difference in the top and bottom readings. From everything I've read the caster should be between 5.5 - 6.5 for the best on road driving. I have an appointment to get it aligned next Monday so should I leave it until I have real numbers or shorten the LCA just a little? Could it also be the toe in after lifting that's causing it to drive a litte different?
If you got 0 at the holes on the front axle then you are at 6 degrees. These holes (green circles) in this pic.

https://www.jlwranglerforums.com/forum/threads/jl-rubicon-caster-measure.25691/#post-609860


372CE781-377E-4091-BCFC-8B62921C1349.jpeg
 
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Hale2016

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Hale2016

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If I were having it professionally aligned on Monday I would not worry about it.

But it’s not my wife’s DD.

How ling were the arms you removed?
I had the Mopar LCA and they're 24.25'' but it seemed to drive slightly better with them which is why I suspect that maybe I have the new ones too long.
 

hoag4147

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Yes that's where I got zero but not sure how accurate my level is. I also checked it with my Iphone and would get zero or -1 depending on how I held it.
Should be good. Did you do Adj track bar on front?
 

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I had the Mopar LCA and they're 24.25'' but it seemed to drive slightly better with them which is why I suspect that maybe I have the new ones too long.
Oh. So you had these on first? I thought you added mopar lift and adj LCAs same time. Sorry to keep peppering you with questions. Did you change tires/wheels (larger) after install of LCAs or did you already ha e them? Just trying to rule out any changes
 

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I would adjust them to the length Clayton suggest in the install instructions which is 24.314 for their 2.5 inch lift or to the Mopar lca length which measure 24 1/4. You may have too much caster at 24.5.
If you are getting an alignment at an off-road shop you could alway wait until then.

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Hale2016

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Oh. So you had these on first? I thought you added mopar lift and adj LCAs same time. Sorry to keep peppering you with questions. Did you change tires/wheels (larger) after install of LCAs or did you already ha e them? Just trying to rule out any changes
Yes had the Mopar arms on initially while I was waiting for the Claytons to arrive. I drove it for about a week before changing to the Clayton LCA.
 

hoag4147

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Yes had the Mopar arms on initially while I was waiting for the Claytons to arrive. I drove it for about a week before changing to the Clayton LCA.
Okay. I know chart above basically states 24 5/16s for 2.5” lift I still wouldn’t go below 24 3/8s if you got 2.75” lift. Best bet is to prob get all specs after alignment. Hopefully it is an offroad shop doing it. Others will prob try to lower caster to within specs. Definitely want to get 6.0-6.5 like you have read already.
 

Clayton Off Road

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I have a 2021 Rubicon Unlimited and I installed the Mopar lift kit which gained me 2.75'' of lift. The Jeep drove decent with this lift as is but from researching I decided to add adjustable lower control arms. I purchased the Clayton Overland Plus LCA and set them to 24.5'' and now the Jeep seems to wander more and the wife is not happy since it's her daily driver. I'm thinking that I may have the LCA set too long based off of a cheap digital level that I have. Let me stress again this is a cheap digital level so I don't know how accurate it really is. I took the following measurements and got these results.

Top ball joint 8 degrees
Bottom ball joint 9 degrees
Flats on rear end housing 0 degrees

My level sit better on the bottom ball joint so I think that's the difference in the top and bottom readings. From everything I've read the caster should be between 5.5 - 6.5 for the best on road driving. I have an appointment to get it aligned next Monday so should I leave it until I have real numbers or shorten the LCA just a little? Could it also be the toe in after lifting that's causing it to drive a litte different?
For the amount of lift that you have, we would recommend setting the front lower arms to about 24.25 for best results. This is also part of the reason that we always suggest going with a set of front upper adjustable control arms, rather than the front lowers when looking for better road manners, as the lower arms are better for setting axle position or wheelbase, and front uppers are best for adjusting caster. You can still achieve proper caster by using the lower arms, it's just a little bit more difficult trying to find the right balance. If you're still having any problems after your alignment, give us a call and we can go over your current setup and make suggestions accordingly!

For anybody looking for a great entry-level system like the Mopar kit, but that also provides everything you need for proper suspension geometry so that your vehicle still rides like it did stock, take a look at our Ride Right suspension systems!

https://www.claytonoffroad.com/product/jeep-wrangler-25-ride-right-lift-kit-4dr-2018-jl
 
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Hale2016

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For the amount of lift that you have, we would recommend setting the front lower arms to about 4.25 for best results. This is also part of the reason that we always suggest going with a set of front upper adjustable control arms, rather than the front lowers when looking for better road manners, as the lower arms are better for setting axle position or wheelbase, and front uppers are best for adjusting caster. You can still achieve proper caster by using the lower arms, it's just a little bit more difficult trying to find the right balance. If you're still having any problems after your alignment, give us a call and we can go over your current setup and make suggestions accordingly!

For anybody looking for a great entry-level system like the Mopar kit, but that also provides everything you need for proper suspension geometry so that your vehicle still rides like it did stock, take a look at our Ride Right suspension systems!

https://www.claytonoffroad.com/product/jeep-wrangler-25-ride-right-lift-kit-4dr-2018-jl

Not sure what you mean by 4.25?
 

gato

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OP, did you do your alignment at an off-road shop? Where is your caster at?

I have a little bit over 3" of lift on my Rubicon (Mopar lift + 0.75" spacer) and my Jeep driver perfectly fine with the Mopar LCA. My caste is about 5.5.

Because of the early steering problems on 2018-2020 JLs (due to bad steering gear, bad track bar ends, bad steering stabilizers, etc) there is a bias on this Forum for people to add a lot more caster and longer LCA to JLs.

Please note: More caster is not generally better. Specially Caster over 6 deg. Also, adjustable control arms can add more cross-caster differences if not set up correctly, which has it's own downsides.

You should not have your LCA much longer than 24 and 1/4. Maybe 24 and 5/16 or 24 and 3/8s tops. But 24 and 1/4 is prob best. And I agree with Clayton (same advice also from Icon and others). If you ever need to adjust caster, use adjustable UCA.
 
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