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 forged Johnny Joints for fabricators and suspension system builders offer 30 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 bushings that encase 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 1/2 in. diameter, fitted with a zerk fitting for greasing, 2 1/4 in. of 1 in.-14 left hand threads on the shank, and a 2.365 in. mounting width ball with a .484 in. thru bolt hole. Finished in gold zinc plating.
| Brand | RockJock |
Reviews of Core 4x4
5.0
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132 reviews
SG
Sal Giordano
Sep 24, 2025
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I want to take the time to share my experience with Core 4x4.
I have a 2004 Jeep Wrangler and was looking to upgrade some suspension parts. I went with Core 4x4 upper & lower adjustable control arms and a front adjustable track bar. Everything arrived quickly, and right out of the box I was impressed with the quality and craftsmanship.
I had a few questions during installation (measurements and torque specs), and I spoke with Korby on a couple of occasions. Not only did he send me detailed instructions, but he also shared an installation video specific to the part and vehicle I was working on, something you don’t get from many companies.
The control arms fit perfectly, look great, and perform exactly as I hoped. I did run into an issue with the front track bar touching the front diff. When I reached out, Korby had me send pictures and then immediately offered two solutions: his bar guy could make a different bend and send it out to me, or I could get a full refund. His response honestly blew me away. As much as I wanted to run the Core 4x4 track bar, I chose the refund. Korby sent me a prepaid shipping label right away, no hassle.
My experience with Core 4x4 has been excellent. Korby was extremely understanding, communicative, and helpful every step of the way. The parts I received were high quality, and the customer service was second to none.
I would absolutely recommend Core 4x4 10 out of 10 times and will be using them again. Just a great American company with awesome people who truly care about their customers.
Thank you Korby, and thank you Core 4x4!
JW
Jonathan Word
Aug 25, 2025
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Beefy parts made and painted well, very fair pricing for what you get, and fantastic customer service to boot. Easily my favorite place to get suspension parts.
MV
Mr. V
Mar 24, 2021
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Good quality parts, much stronger than stock
MM
MIKE (Mike the Mechanic)
Jul 26, 2025
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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.
LS
Leonard Smith
Jan 22, 2026
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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.
JH
Joe Hu
Sep 24, 2025
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Amazing! I put all my new control arms and it drives a lot smoother and looks great!!!
CD
Christopher Dami
Jun 26, 2025
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2022 I ordered a 2023 Jeep Wrangler Rubicon in High Velocity yellow. Without any hesitation I knew I was going with Core 4x4’s 16pc Camp series suspension, powder coated in yellow. Compliments were a given from any and everyone that looked under my jeep. So beefy, I may have left some yellow paint on the rocks from Maine to Florida, but no bends or breaks. Customer service has been perfect each and every time I have needed something. Their warranty is top notch! Their communication is also wonderful. Might upgrade to the Crawl Series control arms where the Johnny joints are on both sides. Great all around company and a great team to troubleshoot your issue and come to a conclusion. Nothing bad to say about this company. Just love this suspension.
A
Adam
Oct 24, 2025
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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!
ST
Sal Torres
May 27, 2025
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upper control arms look great and went on easy.. only reason I gave 4 stars and not 5 is because of a shipping issue which put my build a week behind. The issue was resolved quickly and painlessly, great customer service. Only time will tell how control arms perform but they look great and like they will go above and beyond control arm demand.
CM
Cameron Masters
Mar 24, 2023
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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.
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Specifications
| Brand | RockJock |