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RockJock Sport Edition Johnny Joint Suspension System for JL Wrangler w/ 392 Hemi, 3.5 in. lift

RockJock Sport Edition Johnny Joint Suspension System for JL Wrangler w/ 392 Hemi, 3.5 in. lift
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2,876.00 2876.0 USD 2,876.00

2,876.00

Not Available For Sale

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RockJock Sport Edition Johnny Joint Suspension System for JL Wrangler w/ 392 Hemi, 3.5 in. lift

RockJock Sport Edition Johnny Joint Suspension System for JL Wrangler w/ 392 Hemi, 3.5 in. lift
SKU: RJ-JL3920-101
Pick your vehicle to confirm fit

2,876.00 2876.0 USD 2,876.00

2,876.00

Not Available For Sale

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Alignment recommended Lifetime warranty Made in USA

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 Sport Edition Johnny Joint Suspension System for JL Wrangler Unlimiteds (4-door) with the 392 Hemi engine provides 3 1/2 inches of lift and allows for efficient clearance of up to 37 in. tall tires (with minor trimming, larger tires will require aftermarket fenders). This kit is comprised of only the highest end components in the areas of strength, fit, finish, function, and the engineering to back them. This kit is more than sufficient for those who want to lift their vehicle, install big tires and hit some trails on the weekend! Included in this kit are front upper and rear upper Johnny Joint adjustable control arms, set of 4 progressively wound coil springs including one front and one rear coil spring shim, front (392 specific) and rear bump stop kits, Johnny Joint adjustable front trac bar, 392 specific rear trac bar geometry relocation bracket, front and rear adjustable extended sway bar links and front brake line relocation brackets. For those who intend to do more serious 4 wheeling and rock crawling, you'll want to look at all of the upgrade parts that RockJock has to offer that can be added to this kit to get your vehicle to it's full potential. Next level offerings such as Johnny Joint lower control arms, Antirock Sway Bars and Currectlync Heavy Duty Steering are a must for serious off-roading! Shock options to suite this kit are available from all of the top suppliers.

Make Model Submodel Years
Jeep Wrangler 2018 - Present

Vehicle Jeep Wrangler JL / JLU (18–Present)
Brand RockJock
Google

Reviews of Core 4x4

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5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
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Leonard Smith Jan 22, 2026
Google
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.
OJ
Oldgreg jr Mar 23, 2025
Google
Good company, they offer well built parts and Great customer service. I had a couple of hang ups with my control arms that I purchased, they were very easy to work with and found the solution to make them work.
DR
David Rogers Aug 25, 2025
Google
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)
Review photo 1 Review photo 2
OK
oleg k Nov 23, 2025
Google
I recently ordered a set of control arms from Core 4x4, and the entire experience was absolutely top-notch from start to finish. The ordering process was smooth, the parts arrived quickly, and the control arms themselves are extremely high quality—solid construction, great finish, and clearly built to last. I also want to give a special shout-out to Korby, the guy I spoke with during the process. His customer service was amazing. He went above and beyond to make sure I got exactly what I needed, answered all my questions, and made the whole experience stress-free. You don’t see service like that very often these days. If you’re looking for high-quality suspension components backed by truly exceptional customer service, I highly recommend Core 4x4. I’ll definitely be buying from them again.
RP
Robin Poole Jul 26, 2025
Google
I had several questions before my purchase and Korby helped me with the correct parts to order and recommendations. Outstanding customer service and product knowledge! Can't wait to install them!
JM
Jason Mitchell Dec 8, 2025
Google
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.
FS
Fernando Salazar Aug 25, 2025
Google
Great quality control arms and great customer service. Korby has been a great help at answering my questions on some issues I’ve been having with installation!
S
Sebastian Oct 24, 2025
Google
Great products they sell, got a crawl series long arm kit for my xj and it has held up quite nice, they are beefy, and for what ever reason they fail it has a great warranty with a customer service to match, when someone asks what control arm kit to buy I always recommend core 4x4
JF
jacob fezza Mar 24, 2022
Google
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
BZ
Brandon Zeiders Dec 23, 2025
Google
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!

Specifications

Vehicle Jeep Wrangler JL / JLU (18–Present)
Brand RockJock
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