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 1 in.-14 left hand thread jam nut for use on RockJock Johnny Joints with treaded shanks, or in any other application that would need a 1 in. jam nut. Gold zinc plated, sold each.
| Brand | RockJock |
Reviews of Core 4x4
5.0
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132 reviews
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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!
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89Patriot
Jan 22, 2026
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Great company! I have used there products consistently with no complaints with quality you can see and feel. From my experience, their customer service is also amazing. Core 4x4 has no issues standing behind their already amazing products and will quickly and professionally solve issues may they arise. I will continue to be a customer.
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 ! ! !
GC
Grant Chaisson
Jun 26, 2025
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These guys are awesome!! They have helped me build multiple jeeps from zjs to mjs and now with my lj build they all ways impress.
There products are the best on the market in my eyes. The best part about it all is it's all made right here in american and shipped anywhere in the world 🌎 .
Don't think twice when your looking for control arm or lift kits for your vehicle if these guys sell it BUY IT!!!
PM
Paul Melancon
Aug 25, 2025
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Ordered a control arm and track bar kit for my WJ from Core 4x4 on Monday 7/28 and received it today, Friday 8/1. Im not a state or two away, im in CT aka the other side of the country. Communication is phenominal, emails were responded too in an hour or less. Parts arrived well packed, not damaged, and are great quality for my needs. There arent many companies left that service customers as well as Core 4x4 and i wont hesitate to check them out again if i need something else. Well done!
JS
Jeffrey Shafer
Jan 22, 2026
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Exceptional customer service. All my questions were asked in a timely manner and parts were replaced when an error occured. I encourage people to make purchases due to their exceptional quality products, but also because of their customer service. Will make additional purchases in the future.
JT
jacob trice
Apr 27, 2025
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Core 4x4 has outstanding products at a fair price and unmatched customer service. When you call Korby, it's like talking with a friend. Very cool and helpul!
I ordered some custom control arms, but from the wrong product line and they were super cool about returning them and upgrading to a better "Crawl" series. Only charged the difference between the two products. They paid all the return shipping and sent the uprgaded arms super quick. It was only a couple days. Awesome!!
I couldn't be happier with the transaction👍🏼
Also, these control arms are stout and take a beating. I run heck out my Jeep in the rocks and desert. No problems whatsoever.
Thanks Core 4x4, ya'll are welcome at my campfire anytime!
Jake T.
Pleasant Hill, Or.
JA
Jonathan Aguilera
Jan 22, 2026
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Great experience with Core 4x4! I purchased some suspension parts for my dad's 98 Jeep TJ. The products they make are super durable and look even better in person. Attention to detail and overall superior quality. The staff at Core 4x4 is super helpful also, Korby has been great. Updating me on the status of my order and sending me tracking numbers as well. Thank you all at Core 4x4, keep up the amazing work!
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!
RD
Reagan D'mello
Dec 23, 2025
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Love the product. Excellent customer support 👍🏽 …
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Specifications
| Brand | RockJock |