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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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2,728.00 2728.0 USD 2,728.00

2,728.00

Not Available For Sale

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Fitment guarantee Ships from Orem, UT 4–8 hr install
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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

2,728.00 2728.0 USD 2,728.00

2,728.00

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
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Reviews of Core 4x4

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5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
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Adam M Sep 24, 2025
Google
First time buying from Korby @ Core 4x4 and it’s being nothing short of a great experience. I bought the non adjustable Trail kit for my 5th Gen Ram 1500 with a 2” lift. The welds look great, nice powder coat finish and quality bushing. Had some trouble fitting the grease nipples due to the powder coating but a thread tap would fix that. They fit easily and perform great. I felt the improvement straight away. No more wheel hop on hard acceleration which was my main reason for the purchase. I was missing some smaller bushings needed for the 5th Gen and Korby’s custom service was on point, with responsive emails and mailing out the missing parts straight away. Very happy with their products and customer service. Highly recommended company👌🏽
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JG
James Griffin Jul 26, 2025
Google
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.
Review photo 1
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Todd Hume Jan 22, 2026
Google
Their products are great but the service is even better!! Thanks Korby.
VK
Victor Keele Sep 24, 2025
Google
Great customer service. I got my front upper and lower control arms and hardware on Friday afternoon. It didn’t come with instructions so I called Core 4X4 and they immediately e mailed me the instructions. Also, the kit I got had the spacers missing so I called. It was late Friday by thus time but they took care of the issue first thing Monday morning and I got the spacers on Tuesday. Great company.
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Robert Van Gorder Apr 27, 2025
Google
Amazing service. Bought a track bar through Americantrucks.com and they sent it with the wrong size bushing sleeve. Korby at Core 4x4 was quick to get me the correct size and very responsive. Will definitely be using more of their stuff.
CW
Cody Whitlock Sep 24, 2025
Google
10/10 overall experience, shipping, customer service, and such a great product!
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Norb Pranger Oct 24, 2025
Google
Not sure where to start, Products or Service or Warranty. Products: I found Core4x4 through a very respected YouTuber in the Jeeping community. I purchased an entire set of Core4x4 Control Arms three years ago and have beat the daylights out of them and they are still in great condition. Now, I purchased another Jeep, this time for my daughter and bought yet another set of Control Arms because I know that these things can take a beating and stand up to it. I plan on replacing more parts on this TJ and my JL and will continue to buy from Core4x4. Service: This isn't some huge name conglomerate that treats you like you're just another customer. They are quick with responses and will always make things right should something be a problem. Oh and the quickness in which they ship their products is unmatched. I bought these CAs for my TJ on Thursday, I received them on Monday. Most other manufacturers will tell you weeks, they had them to me in 2 shipping days. Warranty: Seriously, a lifetime warranty? Yes please. Nothing more to say. I can't say enough about how great of a company this is. I've even spoken to the owner through email a few years back on some questions that I had. Support small American built businesses. P.S. Core 4x4, feel free to make me an ambassador and send me some swag :) .
BA
bryan angell Jun 26, 2025
Google
First off amazing products. I got a set of adjustable control arms for my XJ and it is so nice to be able to dial in caster and pinion angles. A quick call and I was able to purchase an adjustable track.
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DA
Dastrup Auto Mar 25, 2019
Google
I have bought a bunch of sets of arms, track bars and even had custom work done by Core 4x4. Just yesterday, Spence and Cam delivered an awesome cross member they designed and built for me! All of their products have been exceptional! I have personally seen their progression with design changes/updates. They truly take pride in their work and products. Quality control is second to none! They’ve also helped me diagnose issues with different jeeps I’ve had, as well as Dodge/Rams. These guys know their stuff! Really! I trust them whole heartedly and absolutely love their products/quality of work! I’ve referred many people, and will always continue to do so. Keep up the good work Core4x4!
C
Chris Oct 24, 2025
Google
Great product for a good price. Customer service is top notch, I had an issue which was self cause and Core 4x4 helped me out even though it was my own fault. Would definitely recommend and use them again.

Specifications

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