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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%
JI
Jerome Segura III Jun 26, 2025
Google
I bought the 16pc Cruise Series Adjustable Control Arm, Track Bar, Steering, End Link Kit to replace a worn budget 4" lift on my used JKU. These are top quality parts; very solid. Customer service is unsurpassed. They even matched prices on my order placed before the tax day sale. I made an error in ordering a drag link flip kit; they were quick to help me fix this too. There's peace of mind knowing these components are made in the USA. Thank you. 👍👍
Review photo 1 Review photo 2
MH
mark hinz Mar 2, 2026
Google
Went above and beyond to get the parts we needed to complete our customers build for Moab Easter safari cant thank you enough for all your hard work and efforts Thank you and look forward to working with you in the near future
N
niceguyr1 Mar 24, 2023
Google
I purchased upper and lower adjustable arms for my WJ and lowers were missing the spacers. I didn't know until 3 months later when I was installing them. With absolutely zero hassles they quickly sent me the missing spacers. Fantastic product and service! Huge thank you guys for the awesome service and parts!!! Customer service is quickly becoming a lost commodity and you guys gave me hope that it's still alive and well, you just have to buy from the right people... Thanks again for going above and beyond! 👍👍
DN
Devan Nelson Mar 25, 2019
Google
Had a great experience with Core 4x4, I desperately needed a custom track bar and found out just a couple days before Easter Jeep Safari. Spence was a huge help and made it happen with plenty of time to spare. Their parts are top notch!
WT
William Turton Nov 23, 2025
Google
Finally a company with a great product and customer service to match. I changed my order last minute from short arms to long arms. The lift is extremely well built. Korbey was awesome! Highly recommend Core 4x4
RP
Robin Poole Jul 26, 2025
Google
I had several questions before my purchase and Korby helped me with the correct parts to order and recommendations. Outstanding customer service and product knowledge! Can't wait to install them!
EL
Eric Labrum May 27, 2025
Google
Best customer service I have ever experienced. They are my go to source do to quality and service
EC
Eric Cox Jul 26, 2025
Google
Prompt, professional, and courteous service! Quality parts and broad assortment of products to suite your 4x4 needs:)
CM
Cameron Masters Mar 24, 2023
Google
Absolutely incredible family owned business. I asked to pick up my order since I’m local and they came in on a weekend to accommodate. Had to make some adjustments to parts and took the time to make sure it was perfect. Parts are incredible quality. If you have a Jeep, do not hesitate to support this local business.
M
Matt Mar 23, 2024
Google
The best products on the market. 95% of my xj is core 4x4 products

Specifications

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