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 1 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
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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!
RH
Rex Hodges
Jun 26, 2025
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After ordering an upper and lower adjustable control arm kit manufactured by CORE 4X4 from a jeep parts distributor who's intials are E.T., they came with 3 of the threaded ends missing. After over 2 months of phone calls and emails to this E.T. company nothing was resolved. I finally decided to call CORE 4X4 myself and tell them my dilemma. I spoke with a very personable and professional gentleman named Korby, who is one of CORE 4X4's representatives, after a brief discussion of what I went thru he simply asked me for a picture and some measurements and the items I was missing and asked if I could cover ONLY the cost of shipping and I had my missing parts in exactly 1 weeks time. This company not only builds all it's parts in the U.S.A., they stand behind their products with great customer service and life time warranty. My experience with this company and their Rep Korby was fantastic. I would definitely recommend CORE 4X4 to anyone who needs parts for any 4x4 projects. You just can't beat their quality and service.
Rex Hodges
Valparaiso, Indiana
DR
David Rogers
Aug 25, 2025
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Ive had the front adjustable control arm kit in bright green for my 1996 ZJ.
Ive had the kit for about a year now and i have to say, im extremely impressed, over 1000 miles off-road and roughly 20,000 miles on the highway. These control arm kits for any vehicle built by core 4x4 are well worth the money, just be aware thereight be some minor scatches or chips from shipping ( but who should care about that if you're beating the crap out of em' they way they were built and designed for)
SC
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.
WT
William Turton
Nov 23, 2025
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Finally a company with a great product and customer service to match. I changed my order last minute from short arms to long arms. The lift is extremely well built. Korbey was awesome! Highly
recommend Core 4x4
RH
Roger Hooks
Jun 26, 2025
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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!
BM
Brantly Musgrave
Jan 22, 2026
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First and foremost would like to say that Core4x4s customer service is top notch and they definitely stand behind their warranty on products! Highly recommend using them for any of your off road needs! It’s rare to find a company now a days that backs their products and they do!
Had a few issues with mounts and control arms and they handled it without hesitation! Thank you!
EC
Eric Cox
Jul 26, 2025
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Prompt, professional, and courteous service! Quality parts and broad assortment of products to suite your 4x4 needs:)
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.
MP
Mirko Pompili
Mar 19, 2026
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I want to share a truly positive experience.
I ordered a car kit consisting of two packages, but unfortunately one was lost during shipping with UPS. The situation could have become complicated... but it didn't.
The company manager was extremely helpful and professional: he personally followed up on the situation and did everything he could to resolve the issue, even sending me the package again without hesitation.
It's rare to find such attentive and reliable customer service these days.
My sincere congratulations on your professionalism and commitment: that makes all the difference.
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Specifications
| Brand | RockJock |