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 in. diameter, fitted with a zerk fitting for greasing, 2 1/4 in. of 3/4 in.-16 right hand threads on the shank, and a 2 in. mounting width ball with a .4375 in. thru bolt hole. Finished in gold zinc plating. This unit also includes a 7/16 in. greasable bolt for external greasing of the joint.
| Brand | RockJock |
Reviews of Core 4x4
5.0
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132 reviews
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niceguyr1
Mar 24, 2023
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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! 👍👍
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.
JO
Jaime Overmyer
Nov 23, 2025
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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!
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Chris
Oct 24, 2025
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Great product for a good price. Customer service is top notch, I had an issue which was self cause and Core 4x4 helped me out even though it was my own fault. Would definitely recommend and use them again.
PG
Paul Griffin
Feb 21, 2026
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Great long arm kit with everything else I needed as well! They worked with me to ensure that I was getting an upgraded components kit just like I wanted. Fast shipping with some of the best packaging that I have ever seen. Nothing was scratched or missing and this kit is even more impressive than the videos or website can show. Powder coating looks great with no issues.
I would highly recommend CORE 4x4 to anyone looking for a great quality kit.
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.
PB
Peter Busack
May 27, 2025
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Purchased a set of Trailing arms for my Ram 1500, quality is first class. I bought the ones with the Jonny Joints for more articulation and it appears from the construction I should get a lifetime of use, Zerk fittings are an added plus. Would defiantly recommend, and the the service team answered all of my questions.
RP
Robin Poole
Jul 26, 2025
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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!
EG
Erica Grissom
May 27, 2025
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First off, I wish I knew about them sooner. The customer service is top tier. The response time is about 30 min no waiting 1-3 days to get a response. The parts are heavy-duty and look amazing. The packaging is perfect, I can't wait to hit some trails. Thanks Core4x4
GK
GLENN KOSZKA
Apr 27, 2025
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The folks at Core 4X4 are always wonderful to deal with. They explain your options and never pressure or rush things. The quality of the Core Control Arms is top shelf, especially if your goal is to stop wheel hop. I recommend Core 4x4 without reservation ! ! !
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Specifications
| Brand | RockJock |