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Control arm length with geo brackets

Lunentucker

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Adjustable arms allow you to adjust caster but do nothing to correct the geometry. With 4" of lift you'll have good caster and bad control arm angles. Better than bad caster AND bad control arm angles, but still not as good as having both good. We run Adjustable lowers with drop brackets as I prefer closer to 7⁰of caster.
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Wheelin98TJ

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Adjustable arms allow you to adjust caster but do nothing to correct the geometry. With 4" of lift you'll have good caster and bad control arm angles. Better than bad caster AND bad control arm angles, but still not as good as having both good. We run Adjustable lowers with drop brackets as I prefer closer to 7⁰of caster.
TJs with much shorter ~16” lower arms and 4” of lift could be setup well and drive awesome on the street without drop brackets. ?
 

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TJs with much shorter ~16” lower arms and 4” of lift could be setup well and drive awesome on the street without drop brackets. ?
It’s all relative, as they say.
Drop brackets will Improve the street ride, no exceptions. Adj arms on top of that will let you dial in caster, as well as center the tires in the wheel wells. I’d use the lowest bolt hole as long as the arms can adjust short enough to correct those other things.
 

Zachanadandy

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TJs with much shorter ~16” lower arms and 4” of lift could be setup well and drive awesome on the street without drop brackets. ?
I think you spelled OK wrong? A short arm tj drove awesome on the street when? Granted with the top off it didn't have the power to drive actual freeway speeds so you aren't even comparing apples to apples. Nobody is saying the JL or JT are undeliverable without do brackets, but better it better period. I'd argue a JT with a 4" spacer would still drive better than any short arm tj but clearly that isn't optimal.
 

Mays9185

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Per rancho they said keep them stock length and use the holes to adjust caster.
 

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Wheelin98TJ

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I think you spelled OK wrong? A short arm tj drove awesome on the street when? Granted with the top off it didn't have the power to drive actual freeway speeds so you aren't even comparing apples to apples. Nobody is saying the JL or JT are undeliverable without do brackets, but better it better period. I'd argue a JT with a 4" spacer would still drive better than any short arm tj but clearly that isn't optimal.
Take a short arm TJ built by Currie or Savvy. It will drive awesome on the street.

Outboarded rear shocks, custom valved shocks, spring perches corrected for axle being rotated. There are several things you can do to make it ride as good or better than when it was stock.

TJs will easily cruise at 75-80 MPH. I had one for a DD for many years.

I think the desire to have flat arms is sometimes exaggerated. I wouldn't want drop brackets on something that is wheeled. And I don't see the need for drop brackets with my 3.5-4" or so of lift. It drives fine as it is with adjustable arms.
 

Wheelin98TJ

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Per rancho they said keep them stock length and use the holes to adjust caster.
It's a good starting point, but not a rule of thumb.

If you were using them with a 10" lift, there's a good chance you need arm lengths different than stock.
 

WILDHOBO

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Take a short arm TJ built by Currie or Savvy. It will drive awesome on the street.

Outboarded rear shocks, custom valved shocks, spring perches corrected for axle being rotated. There are several things you can do to make it ride as good or better than when it was stock.

TJs will easily cruise at 75-80 MPH. I had one for a DD for many years.

I think the desire to have flat arms is sometimes exaggerated. I wouldn't want drop brackets on something that is wheeled. And I don't see the need for drop brackets with my 3.5-4" or so of lift. It drives fine as it is with adjustable arms.
I couldn’t agree more. Mine is lifted and on 37’s. With all eight adjustable arms, I’m around 5.6 degrees of caster, my pinion angles are good, in fact my rear pinion is between zero and one degree. It steers perfectly and I can cruise at 80mph with a trailer hooked up, and it’s comfortable and safe. And I can smack my control arms on rocks without worrying about stamped steel brackets breaking. I wouldn’t wheel with drop brackets either. I don’t even like the idea with a daily driver. It’s just adding more connections to loosen up.
 

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I think you spelled OK wrong? A short arm tj drove awesome on the street when? Granted with the top off it didn't have the power to drive actual freeway speeds so you aren't even comparing apples to apples. Nobody is saying the JL or JT are undeliverable without do brackets, but better it better period. I'd argue a JT with a 4" spacer would still drive better than any short arm tj but clearly that isn't optimal.
The biggest drivability issue I have with my TJ on 4" currie JJ's is not so much the short wheelbase but the narrow one - it gets thrown around on the highway by getting sucked into the ruts the semi's make. The JT is defiantly miles above in drivability - of course lacks in other ways though. The JJ's do make terrible ride quality. I'm sure JT's on JJ's are better just because of their overall design, but they absolutely increase NVH.


Take a short arm TJ built by Currie or Savvy. It will drive awesome on the street.

Outboarded rear shocks, custom valved shocks, spring perches corrected for axle being rotated. There are several things you can do to make it ride as good or better than when it was stock.

TJs will easily cruise at 75-80 MPH. I had one for a DD for many years.

I think the desire to have flat arms is sometimes exaggerated. I wouldn't want drop brackets on something that is wheeled. And I don't see the need for drop brackets with my 3.5-4" or so of lift. It drives fine as it is with adjustable arms.
Now a lot of this is very subjective and situational dependent. My TJ with currie 4" and JJ's is absolutely not at all in any way 'awesome' on the street, and it is dialed in perfect. It is awesome off road! It is fine in town at lower speed. On the highway it sucks. Mostly due to the narrow wheelbase, but there is not a chance in he!! I would 'cruise' at 80. I have done 90 in mine to pass someone going 50, but then promptly slowed back to 60. Even 65 on the highways in my area is white knuckle with the TJ, and even with the JT you have to be paying attention. If I'm going up an incline on the highway, I'm lucky to maintain 55. But your profile says Michigan? Wildly different driving situations between there and where I am.....so a lot of it is situational. Roads are quite different around the nation along with topography - this is a critical aspect that almost everyone neglects to consider. The worst thing about the currie lift is the angle of the arms. NVH is horrid. You can't even have a conversation with a passenger on the highway. I can't wait to get rid of the JJ's and go back to a clevite bushing and lower the height.

Drop brackets are awesome - in some situations. My JT rides better than stock, minimal NVH and well planted, and off road performance is perfect for me. I think the comment everyone makes about drop brackets vs. arms 100% revolves around how hard core they are when the statement 'wheelin' comes around - because the term 'wheeling' is also highly subjective, especially since nobody really places a metric on the term. Is wheeling hard core desert racing, or slow rock crawling on the rubicon, or winter snow, or slippery mud or a typical off highway dirt road? All of those situations are significantly different and time and time again the term 'wheelin' is used for all of them. Very difficult trails would for sure smack the drop brackets. But they would also smack on the factory brackets (hence the need for control arm skid plates that some have) if the drop brackets were not there. So it's a moot point. I would rather destroy a replicable drop bracket than a non-replaceable factory bracket welded to the frame. That's a much better method of planning IMO. I have had my JT in a handful of situations where 4wd was required, suspension flexed to the max, but all wheels well planted, and not once came close to hitting one of the drop brackets. So, not trying to argue that your point is invalid, but context needs to be considered with these discussions. They definitely decrease clearance, but by how much and how significant is it? At the end of the day, the pumpkin is still the lowest hanging steel and nobody ever seems concerned about smacking that.
 

Zachanadandy

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Take a short arm TJ built by Currie or Savvy. It will drive awesome on the street.

Outboarded rear shocks, custom valved shocks, spring perches corrected for axle being rotated. There are several things you can do to make it ride as good or better than when it was stock.

TJs will easily cruise at 75-80 MPH. I had one for a DD for many years.

I think the desire to have flat arms is sometimes exaggerated. I wouldn't want drop brackets on something that is wheeled. And I don't see the need for drop brackets with my 3.5-4" or so of lift. It drives fine as it is with adjustable arms.
Drives fine of course. I'm not knocking a quality lift with adjustable arms at all. But short of long arms every lifted jeep on the planet, regardless of kit, will ride better with drop brackets. The flatter the arms the greater the percentage of road forces are transferred vertically into the springs and shocks where they can be absorbed. The steeper the arms the greater the percentage of those forces are transfered horizontally straight into the frame. The flatter the arms the smaller the arc of travel the axle follows throughout the same range of motion. Another point nobody seems to mention, you don't need as much misalignment in the control arm joints to get the same suspension travel if you are starting from flat and traveling through a smaller arc. I've seen countless builds running fancy joints "for better flex" running the same or even shorter shocks than I do? I can use the full 13" of shock travel with stock rear arms and stock uppers in the front, what extra flex are they talking about? It's an easy experiment, take the same jeep, change nothing else, add drop brackets, drive it, report back. The metalcloak brackets are welded and beefy. You'd be much better off dragging them on the rocks than the sheetmetal stock mounts. We've run several 7+ rated trails since adding them and I haven't felt them drag once. They look good as new. Like most, I was skeptical until I tried them. Now I'm ready to run them on every lifted Jeep I'll ever own.
 

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I used to have Johnny joint adjustable control arms on the JT, and they sucked. I can’t say enough about the teraflex apline IR control arms. You get the best of all worlds. No Johnny joints, no jam nuts, and independent rotation on both ends of the arms, but with internal ball joints in rubber, with a traditional steel sleeve encased in it. I’m sure I’m describing it wrong from an engineering standpoint. But the point is that they’re zero maintenance arms with great articulation off road, but Oem-like highway manners. And you don’t need to wait to tighten them until you’re on the ground when dosing or adjusting the lift. They can be torqued to spec with the wheels off the ground. I just wish I’d known about them before the first round.
 

Wheelin98TJ

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The biggest drivability issue I have with my TJ on 4" currie JJ's is not so much the short wheelbase but the narrow one - it gets thrown around on the highway by getting sucked into the ruts the semi's make. The JT is defiantly miles above in drivability - of course lacks in other ways though. The JJ's do make terrible ride quality. I'm sure JT's on JJ's are better just because of their overall design, but they absolutely increase NVH.




Now a lot of this is very subjective and situational dependent. My TJ with currie 4" and JJ's is absolutely not at all in any way 'awesome' on the street, and it is dialed in perfect. It is awesome off road! It is fine in town at lower speed. On the highway it sucks. Mostly due to the narrow wheelbase, but there is not a chance in he!! I would 'cruise' at 80. I have done 90 in mine to pass someone going 50, but then promptly slowed back to 60. Even 65 on the highways in my area is white knuckle with the TJ, and even with the JT you have to be paying attention. If I'm going up an incline on the highway, I'm lucky to maintain 55. But your profile says Michigan? Wildly different driving situations between there and where I am.....so a lot of it is situational. Roads are quite different around the nation along with topography - this is a critical aspect that almost everyone neglects to consider. The worst thing about the currie lift is the angle of the arms. NVH is horrid. You can't even have a conversation with a passenger on the highway. I can't wait to get rid of the JJ's and go back to a clevite bushing and lower the height.

Drop brackets are awesome - in some situations. My JT rides better than stock, minimal NVH and well planted, and off road performance is perfect for me. I think the comment everyone makes about drop brackets vs. arms 100% revolves around how hard core they are when the statement 'wheelin' comes around - because the term 'wheeling' is also highly subjective, especially since nobody really places a metric on the term. Is wheeling hard core desert racing, or slow rock crawling on the rubicon, or winter snow, or slippery mud or a typical off highway dirt road? All of those situations are significantly different and time and time again the term 'wheelin' is used for all of them. Very difficult trails would for sure smack the drop brackets. But they would also smack on the factory brackets (hence the need for control arm skid plates that some have) if the drop brackets were not there. So it's a moot point. I would rather destroy a replicable drop bracket than a non-replaceable factory bracket welded to the frame. That's a much better method of planning IMO. I have had my JT in a handful of situations where 4wd was required, suspension flexed to the max, but all wheels well planted, and not once came close to hitting one of the drop brackets. So, not trying to argue that your point is invalid, but context needs to be considered with these discussions. They definitely decrease clearance, but by how much and how significant is it? At the end of the day, the pumpkin is still the lowest hanging steel and nobody ever seems concerned about smacking that.
I agree, there is a lot of subjectivity here.

It's not often you hear "terrible ride quality" and "absolutely increase NVH" about Johnny Joints. I don't agree with this based on my experience.

The guy behind Savvy Off-Road will tell you he can put an arm with any style joint under your rig and you won't be able to tell the difference.

When you say NVH is horrid and you can't have a conversation on the highway, that leads me to believe your joints are not causing the NVH. You sure it's not the tires or something else?
 

Wheelin98TJ

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Drives fine of course. I'm not knocking a quality lift with adjustable arms at all. But short of long arms every lifted jeep on the planet, regardless of kit, will ride better with drop brackets. The flatter the arms the greater the percentage of road forces are transferred vertically into the springs and shocks where they can be absorbed. The steeper the arms the greater the percentage of those forces are transfered horizontally straight into the frame. The flatter the arms the smaller the arc of travel the axle follows throughout the same range of motion. Another point nobody seems to mention, you don't need as much misalignment in the control arm joints to get the same suspension travel if you are starting from flat and traveling through a smaller arc. I've seen countless builds running fancy joints "for better flex" running the same or even shorter shocks than I do? I can use the full 13" of shock travel with stock rear arms and stock uppers in the front, what extra flex are they talking about? It's an easy experiment, take the same jeep, change nothing else, add drop brackets, drive it, report back. The metalcloak brackets are welded and beefy. You'd be much better off dragging them on the rocks than the sheetmetal stock mounts. We've run several 7+ rated trails since adding them and I haven't felt them drag once. They look good as new. Like most, I was skeptical until I tried them. Now I'm ready to run them on every lifted Jeep I'll ever own.
We all know the theory behind it. The real question is, is the arm angle enough to matter?

There are guys with more experience than us building and testing that say arm angle doesn't matter on reasonable lift heights.
 

Zachanadandy

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We all know the theory behind it. The real question is, is the arm angle enough to matter?

There are guys with more experience than us building and testing that say arm angle doesn't matter on reasonable lift heights.
Like I said simple test. I was amazed the difference the drop brackets made. I have adjustable lowers. Only 3.5" lift. No other changes were made and the lowers were shortened to maintain the same caster. The jeep drives better. Bumps are smoother and there's no feedback through the steering wheel when hitting them either. The idea that arm angle doesn't matter is just dumb. No the arms aren't at a 45⁰ angle on a 3-4" lift, but they are significantly steeper than stock. That means increased arc of travel. It also means the axle is trying to push forward when it is pushed up, making bumps and potholes feel even worse. If the arm was truly flat, it would be pulling away from the impact as it was forced up. Our uppers are actually slightly angled down on the JL with drop brackets. Take 2 fighters, one leans in to every jab they get hit with, the other leans away. Now look at their faces after the fight? Yes it matters. Again I don't think it's a difference of being usable vs useless, but better is better.
 

Wheelin98TJ

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Like I said simple test. I was amazed the difference the drop brackets made. I have adjustable lowers. Only 3.5" lift. No other changes were made and the lowers were shortened to maintain the same caster. The jeep drives better. Bumps are smoother and there's no feedback through the steering wheel when hitting them either. The idea that arm angle doesn't matter is just dumb. No the arms aren't at a 45⁰ angle on a 3-4" lift, but they are significantly steeper than stock. That means increased arc of travel. It also means the axle is trying to push forward when it is pushed up, making bumps and potholes feel even worse. If the arm was truly flat, it would be pulling away from the impact as it was forced up. Our uppers are actually slightly angled down on the JL with drop brackets. Take 2 fighters, one leans in to every jab they get hit with, the other leans away. Now look at their faces after the fight? Yes it matters. Again I don't think it's a difference of being usable vs useless, but better is better.
Again, we all know the theory.

The idea isn't that arm angle doesn't matter. The idea is that arm angle doesn't matter at reasonable lift heights.

Your one simple test may have convinced you, but it's a pretty limited scope. There are guys that do this for a living, they do it on countless rigs, they do a lot more testing than the average Jeeper, and they say arm angle doesn't matter on reasonable lift heights.
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