Best Adjustable Front Upper Control Arms

zachpeakee

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There's a lot of discussion about which arms are best, etc.
While I do understand a lot of it, I'm concerned with FRONT UPPER arms only.

With most Control Arms underneath the TJ/LJ platform, there's typically two 'ends' to consider, which can drive the price up substantially.
However, the front uppers have a solid mount, with a bushing/joint on one end only, so the options become fairly comparable to each other.
(limited by only the single joint, and single vs double adjustable)

I'm having a tough time finding a reasonably priced pair of arms that AREN'T part of a full kit.

Which company seems to have the best reputation, and is there anything specifically to watch out for with front upper arms?

I hate to even ask, because I'm pretty sure I know the answer already, but is something like this Rough Country pair an absolute no-go?
(keep in mind, if the joint blows, there are compatible Johnny Joints that can be swapped in place)

Would love to hear some honest answers on what exactly separates the good from the bad, when dealing with front upper arms.


1707816101238.png
 
I am sure you have heard this statement before, but….. You Get What You Pay For……
The purchase will depend upon how you use your Jeep.
While you may get away with a lesser quality UCA IF you are easy on the suspension, but IF you are hard ob the suspension while off roading; I would look at control arms from Currie, JKS or Saaavy….
 
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Trail Forged also sells by the pair and has front uppers for $225 with a JJ but only single adjustable.

https://trailforged.com/product/front-upper-control-arms-tjljzjxjmjwj/
What I run. Priced right, the best warranty in the business, and I have the benefit of being local to them. Don't get hung up on double-adjustable. You're going to adjust them once during the initial installation, and again if/when you ever change lift height. It's just not that big of a deal.
 
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What I run. Priced right, the best warranty in the business, and I have the benefit of being local to them. Don't get hung up on double-adjustable. You're going to adjust them once during the initial installation, and again if/when you ever change lift height. It's just not that big of a deal.

Says a guy who’s never chased vibration or really dialed in lowers to maximize up travel.
 
There's a lot of discussion about which arms are best, etc.
While I do understand a lot of it, I'm concerned with FRONT UPPER arms only.

With most Control Arms underneath the TJ/LJ platform, there's typically two 'ends' to consider, which can drive the price up substantially.
However, the front uppers have a solid mount, with a bushing/joint on one end only, so the options become fairly comparable to each other.
(limited by only the single joint, and single vs double adjustable)

I'm having a tough time finding a reasonably priced pair of arms that AREN'T part of a full kit.

Which company seems to have the best reputation, and is there anything specifically to watch out for with front upper arms?

I hate to even ask, because I'm pretty sure I know the answer already, but is something like this Rough Country pair an absolute no-go?
(keep in mind, if the joint blows, there are compatible Johnny Joints that can be swapped in place)

Would love to hear some honest answers on what exactly separates the good from the bad, when dealing with front upper arms.


View attachment 500190

It kind of depends on what you are doing with your rig. If you're just driving down a paved or dirt road a rubber bushing on each end is all you need. If you are going to be offroad articulating your suspension then you want something on each end that will allow rotation of the joint. You can study various joints (JJ, RockKrawler, Teraflex, MC) and find very easily that the joint that allows the most horizontal and vertical rotation is a JJ. If you don't have sufficient rotation for your application then it will stress the bushings and the brackets, causing premature failure.

The issue of single vs double adjustable revolves around ease of adjusting the arms for centering the spring perch under the bumpstops and setting the pinion angle. Double adjustable are much easier. I must have changed mine 25 times already due to changing lift heights and chasing vibrations.
 
Double adjustable with Johnny Joints on the frame side. Keep the bushings on the axle side.

Just echoing @jjvw here. Double adjustable, Johnny Joint on the frame side, utilize the bushings on the axle.

Why are yall suggesting to keep rubber bushings in the axle side? It seems like that would cause the one bushing to soak up stresses that would normally be spread across two. I realize the JJ on the other end would remove torsional forces, but lateral front-to-back would still be there, would that not cause excess wear to the bushing?
 
Why are yall suggesting to keep rubber bushings in the axle side? It seems like that would cause the one bushing to soak up stresses that would normally be spread across two. I realize the JJ on the other end would remove torsional forces, but lateral front-to-back would still be there, would that not cause excess wear to the bushing?

From forum learning (@taylormade73 and @mrblaine ) the bushings control the axle better than the 2.0" johnny joint. There have been a few documented issues of Deathwobble resulting from installing the JJ in the axle side of the front upper. It's not a big enough joint or there isn't enough preload. Seems crazy to me that a SINGLE 2.5" joint is fine, but two 2.0" joints are not, but its hard to argue with the results.
 
Why are yall suggesting to keep rubber bushings in the axle side? It seems like that would cause the one bushing to soak up stresses that would normally be spread across two. I realize the JJ on the other end would remove torsional forces, but lateral front-to-back would still be there, would that not cause excess wear to the bushing?

The reason to keep the rubber bushings at the upper axle side, rather than change them to the Johnny Joint upper housing kit is because the little Johnny Joints in that kit are not large enough to sufficiently control the axle. The bonded rubber bushings are preferable in that context.
 
From forum learning (@taylormade73 and @mrblaine ) the bushings control the axle better than the 2.0" johnny joint. There have been a few documented issues of Deathwobble resulting from installing the JJ in the axle side of the front upper. It's not a big enough joint or there isn't enough preload. Seems crazy to me that a SINGLE 2.5" joint is fine, but two 2.0" joints are not, but its hard to argue with the results.

Circles and spheres. The area goes up exponentially as the diameter increases.
 
Circles and spheres. The area goes up exponentially as the diameter increases.

I get that, but the surface area of a two in sphere is ~12.5 sq in (25 for two of them). A 2.5" sphere is ~19.5 sq in. It must have something to do with the bolt hole and shoulder being a larger percentage of the surface on the smaller joint.
 
I get that, but the surface area of a two in sphere is ~12.5 sq in (25 for two of them). A 2.5" sphere is ~19.5 sq in. It must have something to do with the bolt hole and shoulder being a larger percentage of the surface on the smaller joint.

The small is 1.125 diameter and the large is 1.625 diameter for areas of 3.98 and 8.3 less bolt sleeves. Whatever it is, we've never had a single instance of low control with a single upper using the larger joints.
 
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I am sure you have heard this statement before, but….. You Get What You Pay For……
The purchase will depend upon how you use your Jeep.
While you may get away with a lesser quality UCA IF you are easy on the suspension, but IF you are hard ob the suspension while off roading; I would look at control arms from Currie, JKS or Saaavy….

I'm not a firm believer in this 'theory'.
An equal thickness bar, with a johnny joint on the end is the same regardless of whether it is $100 or $500, as long as there are no structural design flaws.

I do understand the quality/structural differences between designs, but some of these are literally the same arms, spread across a $200+ price gap.

Which pulls full circle, to my original question.

Why are yall suggesting to keep rubber bushings in the axle side? It seems like that would cause the one bushing to soak up stresses that would normally be spread across two. I realize the JJ on the other end would remove torsional forces, but lateral front-to-back would still be there, would that not cause excess wear to the bushing?

From my understanding, the front uppers only have one joint.
At least I'm not aware of any way to convert the axle end to a jointed solution, aside from cutting the factory solution off, and welding on a 'tab' fixture for a Johnny Joint. Which in my opinion is overkill, unless I decide to play rev-limiter in the rocks.






I think i've gotten the answers I was looking for.
 
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From my understanding, the front uppers only have one joint.
At least I'm not aware of any way to convert the axle end to a jointed solution, aside from cutting the factory solution off, and welding on a 'tab' fixture for a Johnny Joint.

That is how you get the second, axle-side JJ. Personally, I think I'll stick with the wisdom above and run OE bushings when the time comes.

1707860539043.png
 
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That is how you get the second, axle-side JJ. Personally, I think I'll stick with the wisdom above and run OE bushings when the time comes.

View attachment 500404

THAT to me is where the term "you get what you pay for" hits a dead end.

I understand this solution, however I don't see any additional benefit over the factory style mount for 99% of applications.