RockJock's weld-on 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. The outer shell is weldable .180 in. wall machined DOM tubing that is fitted with a zerk fitting for greasing. This specific joint's 74mm mounting width ball with a 16mm thru bolt hole is designed to fit the frame side of the 2021 and up Bronco's rear control arms.
| Brand | RockJock |
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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.
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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.
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JT JT
Dec 23, 2025
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We have all shopped places where the person on the phone makes you feel like they don't have the time to talk to you the customer or answer your questions. I can tell you first hand that's not Core 4x4. They have the best customer service I have seen so far. They have taken the time to respond to all of my questions in a very prompt and professional manner, taking the time to answer each and every question I have had. Lets put it this way if Core 4x4 sells a product I am wanting for my truck I will buy it from them, I highly recommend Core 4x4.
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Victor Keele
Sep 24, 2025
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Great customer service. I got my front upper and lower control arms and hardware on Friday afternoon. It didn’t come with instructions so I called Core 4X4 and they immediately e mailed me the instructions. Also, the kit I got had the spacers missing so I called. It was late Friday by thus time but they took care of the issue first thing Monday morning and I got the spacers on Tuesday. Great company.
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Jay Miller
Jul 26, 2025
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I purchased a upper and lower set of control arms from core 4x4 they came early then expected and seem to be very nice quality I ran into a complication installing them and emailed them my question I was expecting to get the response maybe the next day because it was after hours I got a response in about a few minutes which allowed me to finish the project that day I super appreciate that, the products are good strong lifetime warranty and their customer service is top notch
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Morgan Griffith
Mar 25, 2018
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I met a couple of the Core 4x4 guys at the Salt Lake Offroad Expo and decided to try them out after noticing one of my control arm bushings was disintegrated. I called to discuss parts on Thursday and I was leaving for a trip on Saturday. These guys built my control arms and had them ready to be picked up Friday, 24 hours later. The parts seem to be great quality and they charged me nothing extra to have them painted. These guys were extremely helpful and without them my trip probably would have been cancelled. looking forward to testing out the arms on my next trip to Moab.
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Craig MacIver
May 27, 2025
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Got the CAMP version of adjustable control arms and track bars for our 03 TJ with a 3” lift and 33x10.5 KO 2’s.
Super beefy bars, great fit and adjustability.
Friendly advice and support from Korby at CORE 4X4. Good follow up as well.
The ride quality is great as well as the handling. I think it all looks pretty good as well.
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Bailey Smith
Mar 23, 2025
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Core 4x4 excels with precision and service and keeps nothing else higher in mind. Everyone I've met at the company is very honest and down to earth, 10/10 would recommend.
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Adam M
Sep 24, 2025
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First time buying from Korby @ Core 4x4 and it’s being nothing short of a great experience. I bought the non adjustable Trail kit for my 5th Gen Ram 1500 with a 2” lift. The welds look great, nice powder coat finish and quality bushing. Had some trouble fitting the grease nipples due to the powder coating but a thread tap would fix that. They fit easily and perform great. I felt the improvement straight away. No more wheel hop on hard acceleration which was my main reason for the purchase.
I was missing some smaller bushings needed for the 5th Gen and Korby’s custom service was on point, with responsive emails and mailing out the missing parts straight away. Very happy with their products and customer service. Highly recommended company👌🏽