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 Front Axle Housing Johnny Joint Kit for TJ Wrangler, LJ Unlimited, XJ Cherokee, MJ Comanche and ZJ Grand Cherokee vehicles replaces the front differential housing upper control arm bushings Johnny Joint rod ends to get maximum articulation out of your suspension! This kit includes a Johnny Joint insert for gear case ear and installation tool, as well as 1 in. thick flame-cut steel upright for the tube side, with the Johnny Joint already installed. This kit has you cut off the top of the stock bracket that is on the tube and install the new RockJock piece into the existing bracket base. You then weld the RockJock piece to the existing bracket base. This allows for no welding to be done on the tube, resulting in no warpage of the tube.This kit requires cutting and welding equipment for installation!!! NOTES: This kit included larger than stock, 1/2 in. greasable hardware for use in performance applications! Control arm holes will have to be drilled to accept the 1/2 in. bolts. This kit is for use on any factory Dana 30 or 44 differential only!
| Make | Model | Submodel | Years |
|---|---|---|---|
| Jeep | Cherokee | 1984 - 2001 | |
| Jeep | Comanche | 1986 - 1992 | |
| Jeep | Wrangler | 1997 - 2006 | |
| Jeep | Wrangler | 2004 - 2006 |
| Brand | RockJock |
Reviews of Core 4x4
5.0
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132 reviews
BC
Brad C
Mar 24, 2021
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Outstanding experience! I asked Core to build me a set of custom control arms that were larger/heavier than they normally build. They gladly accepted the challenge and turned out an expertly crafted and super strong product ahead of schedule. Fit and finish are excellent. Spence and Cameron were a pleasure to work with every step of the way. And all of this for a very reasonable price. I highly recommend these guys!
ST
Sal Torres
May 27, 2025
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upper control arms look great and went on easy.. only reason I gave 4 stars and not 5 is because of a shipping issue which put my build a week behind. The issue was resolved quickly and painlessly, great customer service. Only time will tell how control arms perform but they look great and like they will go above and beyond control arm demand.
JL
John Luna
Nov 23, 2025
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Great team, and help to support my jeep and provide best stuffs
JI
Jerome Segura III
Jun 26, 2025
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I bought the 16pc Cruise Series Adjustable Control Arm, Track Bar, Steering, End Link Kit to replace a worn budget 4" lift on my used JKU. These are top quality parts; very solid. Customer service is unsurpassed. They even matched prices on my order placed before the tax day sale. I made an error in ordering a drag link flip kit; they were quick to help me fix this too. There's peace of mind knowing these components are made in the USA. Thank you. 👍👍
JG
James Griffin
Jul 26, 2025
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Customer service is top notch. They answered all of my questions and got me my tracking number for my packages. I just received both of them and the quality is next level. You guys are truly awesome.
JW
Jonathan Word
Aug 25, 2025
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Beefy parts made and painted well, very fair pricing for what you get, and fantastic customer service to boot. Easily my favorite place to get suspension parts.
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!
JF
jacob fezza
Mar 24, 2022
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I wanted to take a moment and give these guys a shout out, I’ve currently got, for my xj, their adjustable control arms, tier 4 adjustable track bar and adjustable leaf spring shackles. You can always count on a fair price, high quality products, and quick delivery. Keep up the great work guys, will definitely continue to shop with you
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.
TG
Travis Grimm
Mar 23, 2024
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To start off if you're looking to upgrade your control arms definitely hit this company up. Great product, easy install of the product, with three different tiers everything is priced pretty good, I'm a sticker guy and they sent a sticker for each arm each track bar and also three extra ones so the extra are on the Jeep the advertise them for sure. If you're reading this review I highly recommend you to check their website out.
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Specifications
| Brand | RockJock |