Made in USA
Orem, Utah
Lifetime Guarantee
Unconditional
10 Colors
In-house powder coat
Ships in 3 Days
From our UT facility
Fully Adjustable
0-6" of lift
3 X-Series Options
Only Core 4x4
Why Builders Choose Core 4x4
The only aftermarket suspension brand with an X-Series product system
vs. MetalCloak
One price point, no tier options. Core 4x4 Crawl matches their performance at a better price with a better warranty.
Their “lifetime” language refers to their service model. Actual parts warranty: 1 year. Ours: lifetime.
vs. Teraflex
Skip a grease interval? Warranty voided. Core 4x4 Cruise requires zero maintenance — and our warranty covers everything.
Skip a maintenance interval? Their warranty voids. Ours doesn’t.
vs. Clayton / Budget
Cheaper arms exist. But adjustable, American-made, 10 colors, lifetime guarantee, and an upgrade path? Only Core 4x4.
Clayton warrants their Johnny Joints for 90 days. We cover ours for life.
RockJock's greaseable bolts include the grade 8 zerk fitted bolt, 2 flat washers and a stover nut. We use these bolts to grease our Johnny Joint rod ends, but they can be used in numerous applications. This bolt is 7/16 in.-20 thread x 3 1/4 in. long.
| Brand | RockJock |
Select your lift size in Step 1 — the kit ships with the correct geometry for that height. If you’re running a non-standard setup, call us before ordering and we’ll confirm compatibility.
Death wobble is a geometry problem, not just worn parts. Cruise Series corrects caster angle and eliminates the flex points that let shimmy start. Replacing one part at a time delays the fix — this replaces the geometry.
Yes, if you’ve done a lift kit before. Full-day project. Watch the complete JT install walkthrough on our YouTube channel — most owners wrap it in a day. Any off-road shop can run it if you’d rather have it done.
Any non-wear component fails — we replace it. No mileage cap. No maintenance intervals to track. No fine print about voiding if you miss a service. Lifetime means lifetime.
Teraflex’s lifetime warranty voids if you miss a maintenance interval. MetalCloak’s actual parts warranty is 12 months — their “lifetime” language refers to their service program. No conditions here.
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTube
Reviews from Google
5.0
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132 reviews
AP
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.
RC
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.
MT
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.
JJ
Jason Jukich
Jul 26, 2025
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Fast shipping, excellent communication, and awesome products
C
caleb
Mar 24, 2022
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Absolutely a great company. Ordered rear lower control arms with hardware but when i got it the hardware wasn't there but they sent it out right away and got a free t-shirt! Highly recommend.
JM
Jason Mitchell
Dec 8, 2025
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Installed the full kit on my XJ. Ride quality is night and day better than what I had before. The articulation on the trail is insane. These guys know what they are doing. Already recommended Core 4x4 to everyone in my club.
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!
MT
Ma TheMeatLoaf
Mar 23, 2024
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Their website estimated 2 days to get my parts but actually took 11. No communication to let me know what’s going on. Parts were missing. Some days they answer questions, some they don’t. Didn’t let me know I’d have to alter stock bolts to fit their parts.
All around just seems like they don’t care.
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)
BB
Brayden Brockey
Mar 23, 2024
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Got a set of upper control arms for my xj, really impressed with the quality
