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Johnny Joint Uni-Ball for 3-Links. Fits JL, JT Aftermarket Diffs (only) and all JK, TJ, LJ, XJ, MJ and ZJ Stock and Aftermarket Diffs.
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173.00 173.0 USD 173.00

173.00

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Fitment guarantee Ships from Orem, UT 4–8 hr install
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Johnny Joint Uni-Ball for 3-Links. Fits JL, JT Aftermarket Diffs (only) and all JK, TJ, LJ, XJ, MJ and ZJ Stock and Aftermarket Diffs.

Johnny Joint Uni-Ball for 3-Links. Fits JL, JT Aftermarket Diffs (only) and all JK, TJ, LJ, XJ, MJ and ZJ Stock and Aftermarket Diffs.
SKU: RJ-301001-101
Pick your vehicle to confirm fit

173.00 173.0 USD 173.00

173.00

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Lifetime warranty Made in USA

Made in USA Orem, Utah
Lifetime Guarantee Unconditional
10 Colors In-house powder coat
Fully Adjustable 0-6" of lift
3 X-Series Options Only Core 4x4

RockJock Uni-Balls for Front Axle Housings are used in 3-link suspension applications, where the passenger’s side upper control arm has been eliminated and all of the suspension load is now being applied to the one axle housing mounting location. Our Uni-Balls press into the stock bushing holes on the casting side, driver’s side ONLY) of the front differential housing and provide a durable solution that incorporates a 5/8 in. thru-bolt hole for heavier hardware. This Uni-Ball will press into a stock JK or a stock TJ/LJ/XJ/MJ/ZJ housing, as well as aftermarket replacement differentials from companies such as Dana, UD-60s), Dynatrac, East Coast Gear, Fusion 4x4 and Currie Enterprises, cast center housings ONLY, does not apply to 9 in. / fabricated style differentials). Additionally, “most in. aftermarket differentials that are intended for installation in a JL/JT vehicle, still retain the bushing specs. of a JK bushing, making this the applicable Uni-Ball to install in an aftermarket differential, again, cast center only, not 9 in. style going into a JL/JT., for STOCK JL/JT housings, see our RJ-301002-101 Uni-Ball. The mounting width of the center pivoting assembly is 2 in., to allow it to fit into the fork on JL/JT/JK/TJ/LJ/XJ/MJ/XJ front upper control arm, however, the 5/8 in. thru-bolt hole will require drilling of the bolt hole in the control arm fork. Uni-Balls feature a sealed bearing assembly, so no greasing is required. Finish is clear zinc plating.

Make Model Submodel Years
Jeep Cherokee 1984 - 2001
Jeep Comanche 1986 - 1992
Jeep Gladiator 2020 - Present
Jeep Grand Cherokee 1993 - 1998
Jeep Wrangler 1997 - 2006
Jeep Wrangler 2004 - 2006
Jeep Wrangler 2007 - 2018
Jeep Wrangler 2018 - Present

Vehicle Jeep Gladiator JT (20–Present) or Jeep Wrangler JL / JLU (18–Present)
Brand RockJock
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Reviews of Core 4x4

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5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
MN
Mike Nielsen Nov 23, 2025
Google
The customer service is first class. I had an issue with a track bar I installed on my F350. I don’t have any other Core 4x4 parts yet, but with the way I was treated, I know their parts are well done, because they went above and beyond to make sure I was made whole. They wouldn’t be in business if they had to take care of a lot of people like they took care of me. Will definitely be back when it’s time to build the Jeep!
RH
R and H H Oct 24, 2025
Google
Top notch company. Mechanic lost bolts that clamp upper control arms. Korby sent out spare bolts no charge. Best customer service I’ve come across in a long time. Only suspension brand I’ll ever use.
JM
Jay Miller Jul 26, 2025
Google
I purchased a upper and lower set of control arms from core 4x4 they came early then expected and seem to be very nice quality I ran into a complication installing them and emailed them my question I was expecting to get the response maybe the next day because it was after hours I got a response in about a few minutes which allowed me to finish the project that day I super appreciate that, the products are good strong lifetime warranty and their customer service is top notch
JA
Jonathan Aguilera Jan 22, 2026
Google
Great experience with Core 4x4! I purchased some suspension parts for my dad's 98 Jeep TJ. The products they make are super durable and look even better in person. Attention to detail and overall superior quality. The staff at Core 4x4 is super helpful also, Korby has been great. Updating me on the status of my order and sending me tracking numbers as well. Thank you all at Core 4x4, keep up the amazing work!
CM
Craig MacIver May 27, 2025
Google
Got the CAMP version of adjustable control arms and track bars for our 03 TJ with a 3” lift and 33x10.5 KO 2’s. Super beefy bars, great fit and adjustability. Friendly advice and support from Korby at CORE 4X4. Good follow up as well. The ride quality is great as well as the handling. I think it all looks pretty good as well.
Review photo 1 Review photo 2 Review photo 3 Review photo 4
BA
bryan angell Jun 26, 2025
Google
First off amazing products. I got a set of adjustable control arms for my XJ and it is so nice to be able to dial in caster and pinion angles. A quick call and I was able to purchase an adjustable track.
Review photo 1
AS
Anthony Snyder Jun 26, 2025
Google
Great experience and really great parts
D
DSI Jul 26, 2025
Google
Great products with excellent customer service after the sale
N
Nick Sep 24, 2025
Google
I have a 2016 RAM 1500 Crew Cab and I replaced the rear upper and lower control arms also the pan hard track bar and also the sway bar and links for the rear with all I had the articulating bushings. The vehicle now has no body role. They are absolutely incredible if you get the control arms you gotta get the CORE 4 x 4sway bar end links don’t don’t try and be cheap and get Moog or something else you got to get articulating bushings get the core 4 x 4 ones they are the best. My truck drives now through the canyons like a BMW. I have Fox high-performance shocks on there as well with all the CORE 4 x 4 suspension parts and they are amazing. Well worth the money I would highly recommend anybody thinking about CORE 4 x 4 go with CORE 4X4 and if you can go with their articulating bushings, they’re unbelievable drives better now than my Escalades. Well planted no body role and smooth on the Highway unbelievable the difference they all made!! THANKS AGAIN CORE 4x4!!!!
A
Adam Oct 24, 2025
Google
I couldn't have been more excited for the initial unboxing of these new Core 4x4 UCA's! They appear to be so well built and just a true quality product. Installation was a breeze and the initial testing with the forklift appears to have given me some additional flex with less binding on the rest of the components now that the geometry is back properly aligned. Time will tell how they hold up on my near future off-road adventures but I don't have any doubt that they are up to the task!
Review photo 1 Review photo 2 Review photo 3 Review photo 4

Specifications

Vehicle Jeep Gladiator JT (20–Present), Jeep Wrangler JL / JLU (18–Present)
Brand RockJock
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