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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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https://dev.core4x4.com/web/image/product.template/24174/image_1920?unique=de245c6

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

See all on Google
5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
TD
Tim Davis Sep 24, 2025
Google
Customer service is amazing, responds fast and know what they are talking about. Their product looks top of the line.
BW
Brian Wadsworth Jun 26, 2025
Google
Amazing product! Shipping was quick, packaging was great and support was outstanding!!
GH
Gary Haag Aug 25, 2025
Google
Ordered a set of Core 4x4 control arms for my 2006 Jeep TJ. These are some heavy duty quality control arms. Can't wait to get them installed. Great customer service too!
DW
Derek Whitfield Nov 20, 2025
Google
Solid product, the lifetime warranty sealed the deal for me. Installed on my TJ and the ride quality improved noticeably. Shipping took a bit longer than expected but the parts were worth the wait.
MT
Marcus Torres Jan 15, 2026
Google
Best control arms I have installed on any of my builds. After running every major manufacturer, Core 4x4 is on par or better than all the high-end companies at a fraction of the cost. Lifetime warranty is the cherry on top.
MM
Mike Martinez Aug 25, 2025
Google
Phenomenal company - very rare to come by in the automotive industry. Also very impressing. Let me start here. I got a set of yellow sway bar end links for my 19 ram DT (new body style) and let me tell you, I’m hooked. For numerous reasons. One the craftsmanship behind the product is unmatched for sure for without breaking the bank. 2ndly, they stand behind their product. Had a very minor issue and it was resolved in a blink of an eye!!! Insane. Just because of what i listed above i will forever spend my money with core 4x4! And i think you should too! I have no affiliation at all with this company besides being a consumer. I will be ordering my yellow UCAs and the rest of my rear suspension from them here shortly! Korby on the other hand. The representative that helped me went above and beyond FAST. I hung up the phone with him, and with in no lie 3 minutes he was calling back with an answer. GREAT GREAT GREAT customer service, Korby you and core 4x4 are what give us hope in the car community! With much love and great health to you all!!
Review photo 1
SA
Samuel “SamDaman904” Anscher Mar 23, 2024
Google
I meant to put this reviewing about a year ago now, but ever since I’ve had the core 4 x 4, upper and lower control arms on my 2017 ram 1500, they have worked flawlessly leave been on many offering chips, and I’ll definitely be buying new accessories from them in the future and their new upper control arms that they’re offering for all of the ram trucks. Fantastic customer service fantastic health very automotive, off-road, friendly, and any aftermarket thing for your truck or SUV that they currently have!
DT
Dean Tk421 Feb 21, 2026
Google
I purchased the Jeep WJ control arms Camp series over a year ago. Very pleased and impressed. Easy installation and solid build. Bracket broke for rear upper control arm, they redesigned it to be more robust and sent me a new one with hardware, honoring their guarantee!
CT
Canon TeSelle Jun 26, 2025
Google
Great Experience. I wanted to make changes to my order and Korby was more than willing to work with me to get everything corrected. Hope to deal with these guys again in the future.
K
Korosunagi Jul 26, 2025
Google
I broke a grease fitting off in my end link. I thought I was going to have to buy a new one. Reached out to Core 4x4 and wham! bam! They fixed it and sent it back with 2 day shipping. Got it a day early even. If they couldn't fix it they were going to send me a new one. Now that's customer service! They are now a permanent part of my garage. Thank you Core 4x4!

Specifications

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