RockJock's custom machined, right hand thread, weld-in bung for use with forged Johnny Joint rod ends or any other 1 1/4 in.-12 thread rod end. Hex shaped - not round - for ease of bar adjustment. Designed to fit into a tube with a 1 1/2 in. i.d.
| Brand | RockJock |
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTubeReviews from Google
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132 reviews
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Ajay Paynter
Mar 4, 2026
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Great company, who worked with me on shipping parts to arrive in time for a show. When I explained my concern they went above and beyond to make it happen. Quality of the parts is top notch.
RC
Ryan Colligan
Mar 4, 2026
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I have nothing but good things to say about Core 4x4. I have the crawler series on my JKU and we take it all over the place. These parts handle everything we throw at them.
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Marcus Torres
Jan 15, 2026
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Best control arms I have installed on any of my builds. After running every major manufacturer, Core 4x4 is on par or better than all the high-end companies at a fraction of the cost. Lifetime warranty is the cherry on top.
RG
Robert Van Gorder
Apr 27, 2025
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Amazing service. Bought a track bar through Americantrucks.com and they sent it with the wrong size bushing sleeve. Korby at Core 4x4 was quick to get me the correct size and very responsive. Will definitely be using more of their stuff.
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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Gil Valk
Sep 24, 2025
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Excellent service, Prompt responses when needing technical assistance, Amazing looking parts that fit excellently. I would recommend them to anyone looking for suspension components. Also very well packaged when we received the shipment, which means no damage from shipping company!! We went with the Crawl Series double adjustable kit and it definitely looks killer on our build!!!
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Brayden Brockey
Mar 23, 2024
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Got a set of upper control arms for my xj, really impressed with the quality
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Singer Heating and Cooling
Mar 25, 2018
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These guys are great. You can get them on the phone for support. This important and is not always the case with other custom parts builders. Their control arms are bomb proof and offer plenty of options. You can get real genuine Currie Johnny joints without paying the price for Currie arms.
JC
John Cutler
Oct 24, 2025
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In September 2025, we visited CORE 4x4 in Orem, Utah. CORE 4x4 makes control arms and other similar parts that stiffen the suspension of an off-road 4x4 vehicles, so that the off-road vehicles can travel on more rugged terrain. CORE 4x4 used to share this building with another business, and since this other business has moved elsewhere, CORE 4x4 will continue to expand and grow their business. Good for CORE 4x4 to be a growing company and to expand into the vacant part of the building.
JT
Jay Taylor
May 27, 2025
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Had a worn out set of rear upper control arms on my TJ. These were old rubicon express long arms. can’t buy replacements and no one makes a direct fit replacement.
Talked with Korby at core off road sent some measurements and photos and a week later new arms showed up. Packaging was perfect fit was perfect.
Would highly recommend giving these guys a call.