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, single joint) for JL Wrangler, JL Unlimited and JT Gladiator vehicles replaces either front differential housing upper control arm bushing with a Johnny Joint rod end to get maximum articulation out of your suspension! This is a single joint only, see RJ-301000-101 for a complete kit. Finish is zinc plating.
| Make | Model | Submodel | Years |
|---|---|---|---|
| Jeep | Gladiator | 2020 - Present | |
| Jeep | Wrangler | 2018 - Present |
| Vehicle | Jeep Gladiator JT (20–Present) or Jeep Wrangler JL / JLU (18–Present) |
| Brand | RockJock |
Reviews of Core 4x4
5.0
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132 reviews
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Eric Hernandez (savagefit)
May 27, 2025
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The whole process was quick and painless. The products are top tier and when I reached out them for package update info, Korby Linscomb was very responsive, and got me the answers I needed the same day. Even when I emailed back to some additional info, he sent what I was looking for that same day. I love core 4x4 and will be giving them my business from now on.
RR
Ryan Rogers
Aug 25, 2025
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I purchased a set of the Cruiser Series control arms for my Jeep Jk based on postive reviews from different Jeep Facebook pages. Ordered and 2 days later realized they had the very same exact arms on sale in the overstock section. Called them up and they refunded me the savings from my original purchase. Amazing, honest service. Can't wait to get them installed. Keep up the good work guys.
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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!
PM
Paul Melancon
Aug 25, 2025
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Ordered a control arm and track bar kit for my WJ from Core 4x4 on Monday 7/28 and received it today, Friday 8/1. Im not a state or two away, im in CT aka the other side of the country. Communication is phenominal, emails were responded too in an hour or less. Parts arrived well packed, not damaged, and are great quality for my needs. There arent many companies left that service customers as well as Core 4x4 and i wont hesitate to check them out again if i need something else. Well done!
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!
BZ
Brandon Zeiders
Dec 23, 2025
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I ordered the jeep xj long arm lift kit. Control arms showed up first they turned out amazing!! Had some issues with the powder coating on the cross member and sent korby and the team at core4x4 an email. They got right on making me another cross member and sending it out. I appreciate all the help they've given me along the way. Very fast response thru emails. Build quality seems to be pretty dang nice!! Can't wait to install it and enjoy it!
M
Matt
Mar 23, 2024
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The best products on the market. 95% of my xj is core 4x4 products
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.
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.
CW
Cody Whitlock
Sep 24, 2025
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10/10 overall experience, shipping, customer service, and such a great product!
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Specifications
| Vehicle | Jeep Gladiator JT (20–Present), Jeep Wrangler JL / JLU (18–Present) |
| Brand | RockJock |
