Skip to Content
ADD YOUR VEHICLE
Suspension
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.
Pick your vehicle to confirm fit

173.00 173.0 USD 173.00

173.00

See financing options →

Fitment guarantee Ships from Orem, UT 4–8 hr install
ADD TO CART →
https://core4x4.com/web/image/product.template/24174/image_1920?unique=279331a

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

  • Vehicle
    Confirm this matches your vehicle. Use Shop by Vehicle to filter correctly.
  • Brand

Select Color to see price and add to cart.

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
Google

Reviews of Core 4x4

See all on Google
5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
MP
Mirko Pompili Mar 19, 2026
Google
I want to share a truly positive experience. I ordered a car kit consisting of two packages, but unfortunately one was lost during shipping with UPS. The situation could have become complicated... but it didn't. The company manager was extremely helpful and professional: he personally followed up on the situation and did everything he could to resolve the issue, even sending me the package again without hesitation. It's rare to find such attentive and reliable customer service these days. My sincere congratulations on your professionalism and commitment: that makes all the difference.
JO
Jaime Overmyer Nov 23, 2025
Google
Korby was extremely helpful in helping me find the right part for my truck. He was kind, knowledgeable, and patient while I asked a million questions. He also went out of his way to find the right shipping option for me since it’s tricky where I live. I’m looking forward to getting the parts so I can fix my truck and go adventuring again soon!
MV
Mr. V Mar 24, 2021
Google
Good quality parts, much stronger than stock
MS
Mr. Smith Nov 23, 2025
Google
Have yet to get to try them but I bought some upper, and then later , lower control arms for my 03 rubicon. The pricing is very fair, so fair I was hesitant to even purchase. When the product came in I was happily mistaken. These are some beefy units with an incredible warranty! I’m very excited! I went with the “Camp”series as I mostly daily it. I have trouble with the shipping at times when I ordered but Corby is quick to notice things and help communicate the solution. Looking forward to buying more parts!
Review photo 1
MM
MIKE (Mike the Mechanic) Jul 26, 2025
Google
Amazing company and customer service!!!! I messed up on my order and the fixed it immediately. Would definitely recommend them. Can't wait to hit the trails with their product.
MB
Melody Baker Jan 22, 2026
Google
I ordered a part for my 03 Jeep TJ and all I can say is wow! Korby at Core 4x4 is a total rockstar!! There was a glitch with my payment and within minutes, Korby reached out to me to get it fixed, then sent my receipt with the tracking number. I lost the number and reached out to him during the Holidays and got a rapid response with the number again. I can’t say enough about the customer service and the quality of parts. Thank you!!
RC
Robert C May 27, 2025
Google
Fantastic products! Outstanding performance!! Absolutely the best customer service!! You will not be disappointed!
P
Paul Mar 24, 2023
Google
I've been having trouble with the track bar (on my 2nd gen Dodge) since I installed the 3rd gen Synergy adapter bracket and a 3rd gen stock bar.. oddly, they call it a '3rd gen bracket' and the stock 3rd gen bar doesn't quite fit, making contact with the bracket. I had attempted to clearance the bracket but it was still making contact and I could feel it over large bumps. I reached out to a lot of companies, but Core 4x4 offered to make a custom bar for the application with adjustability and dual Johnny joints. The first pass on it didn't work but they sent me out another passenger side end that made it fit incredibly well. This was all done solely over email/descriptions/pictures/measurements. Bar is super high quality and heavy duty, made in the US by a family owned company and carries a lifetime warranty. The customer service was responsive and superb, and the price was a lot less than I expected.
BB
Brayden Brockey Mar 23, 2024
Google
Got a set of upper control arms for my xj, really impressed with the quality
Review photo 1
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.

Specifications

Vehicle Jeep Gladiator JT (20–Present), Jeep Wrangler JL / JLU (18–Present)
Brand RockJock
ADD YOUR VEHICLE Find exact-fit parts
Find →
Pick your series in 30 seconds.
Find My Series →
30-second quiz
Shop by vehicle
Loading…
UNIVERSAL · FITS ANYTHING
DRIVETRAIN Choose vehicle for fit
Drivetrain Coming Soon Axles · Gearing · Driveshafts