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
DW
Derek Whitfield
Nov 20, 2025
★
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Solid product, the lifetime warranty sealed the deal for me. Installed on my TJ and the ride quality improved noticeably. Shipping took a bit longer than expected but the parts were worth the wait.
AL
Andrew LaFave
May 27, 2025
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I am really please with this company. Great product, i had an issue with a couple of the jonnhy joint bushings, they explained what had caused it and how to fix it. Within hrs of receiving my inquiry, i had heard back with the required info I needed. A couple hrs later problem was fixed and ready for the trail again. They care about heir product and their customers. Thanks crew, you rock
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.
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.
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!
J
Justin
Mar 24, 2021
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Small business, family owned, made in the USA, lifetime warranty. Purchased Tier 3 control arms and rear track bar for a 2006 Jeep LJ. Simple website and easy to contact over phone and email. I had some technical questions and they were happy to answer them. They allow local pickup and were built to order same week. The order was wrapped and ready when I walked in and even gave a tour of the shop. They abrasive blast all raw materials to achieve a better surface profile for powdercoat to adhere and create a smooth, durable finish. I also noticed several CNC machines and a robotic welder they use for all their parts. A small outfit with a robotic welder? Their concern for quality is obvious and it shows in the parts they make. Very impressed. Happy to do business with these guys.
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.
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.
BW
Brian Wadsworth
Jun 26, 2025
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Amazing product! Shipping was quick, packaging was great and support was outstanding!!
EG
Erica Grissom
May 27, 2025
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First off, I wish I knew about them sooner. The customer service is top tier. The response time is about 30 min no waiting 1-3 days to get a response. The parts are heavy-duty and look amazing. The packaging is perfect, I can't wait to hit some trails. Thanks Core4x4
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Specifications
| Brand | RockJock |