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's narrow forged Johnny Joints for fabricators and suspension system builders offer 40 degrees of unrestricted movement in any direction as compared to 22 degrees on a common heim joint! Johnny Joint rod ends offer cushioning that a heim joint cannot provide via high-density urethane bushing that encases the inner ball. The heat treated center balls are cross-drilled for thru-bolt lubrication and the joint internals are retained with 2 heavy duty, heat treated side washers and a snap ring. This specific joint is a 2 in. diameter, fitted with a zerk fitting for greasing, 2 1/4 in. of 7/8 in.-14 right hand threads on the shank, and a 1.600 in. mounting width ball with a .562 in. thru bolt hole. Finished in gold zinc plating.
| Brand | RockJock |
Reviews of Core 4x4
5.0
★
★
★
★
★
132 reviews
LS
Leonard Smith
Jan 22, 2026
★
★
★
★
★
I don’t write reviews often, but Core 4x4 absolutely earned this one.
I recently ordered leaf spring mounts and realized after the fact that I messed up my order. Totally my mistake. Instead of giving me the runaround or pointing at a return policy, Core 4x4 emailed me back and forth, worked through exactly what I was doing with my build, and made sure I ended up with the correct parts.
That kind of customer service is rare these days — especially in the off-road world where a lot of companies stop caring once the order is placed.
The parts themselves are exactly what you hope for: solid, well-made, confidence-inspiring hardware that looks like it belongs under a vehicle that actually gets used. You can tell these are designed by people who understand suspension geometry and real-world abuse, not just CAD screenshots.
Mistakes happen — especially on custom or modified builds — and Core 4x4 handled mine like pros. Fast responses, clear communication, and a genuine effort to help me get it right.
If you’re on the fence: don’t be. Core 4x4 is the kind of company you want backing your build — the kind that treats customers like fellow enthusiasts, not order numbers.
OA
Owen Adams
Sep 24, 2025
★
★
★
★
★
These guys are awesome I messed up my address on my order somehow and they were so so helpful Korby was right there every step to a solution very communicative and respectful I will definitely be ordering parts with them in the future!
BC
Brad C
Mar 24, 2021
★
★
★
★
★
Outstanding experience! I asked Core to build me a set of custom control arms that were larger/heavier than they normally build. They gladly accepted the challenge and turned out an expertly crafted and super strong product ahead of schedule. Fit and finish are excellent. Spence and Cameron were a pleasure to work with every step of the way. And all of this for a very reasonable price. I highly recommend these guys!
CT
Canon TeSelle
Jun 26, 2025
★
★
★
★
★
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.
P
Paul
Mar 24, 2023
★
★
★
★
★
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
★
★
★
★
★
Got a set of upper control arms for my xj, really impressed with the quality
HK
Harold Kruder
Mar 23, 2024
★
★
★
★
★
I needed some parts and had to replace 1 lower control arm and their customer service is great. Helped with answering my questions and got parts shipped quickly.
RH
Roger Hooks
Jun 26, 2025
★
★
★
★
★
2018 Ram 2500 Rear Control Arms and Rear track Bar been running for about a year, Great Solid Products and great one on one customer service, same day response with issue resolved!
Thanks Korby!
TG
Travis Grimm
Mar 23, 2024
★
★
★
★
★
To start off if you're looking to upgrade your control arms definitely hit this company up. Great product, easy install of the product, with three different tiers everything is priced pretty good, I'm a sticker guy and they sent a sticker for each arm each track bar and also three extra ones so the extra are on the Jeep the advertise them for sure. If you're reading this review I highly recommend you to check their website out.
DW
Darin Wuebbels
May 27, 2025
★
★
★
★
★
Thanks for the fabulous customer service. Your products and customer service are first class. I highly recommend these guys. Excellent experience.
Your Dynamic Snippet will be displayed here...
This message is displayed because youy did not provide both a filter and a template to use.
Specifications
| Brand | RockJock |