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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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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

2,876.00 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
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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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RM
R2d2 Movi78 Feb 21, 2026
Google
I’m extremely impressed with Core 4x4. The quality of their parts is outstanding — everything feels solid, well‑built, and engineered with real attention to detail. Shipping was fast and everything arrived perfectly packaged. Their customer service is just as good as their products: responsive, helpful, and genuinely committed to making sure you get exactly what you need. Overall, a top‑tier experience. I’ll definitely be buying from them again. Specially thank you Mr. Linscomb from Core 4x4. Arturo M.
TR
Tim Reigies Mar 25, 2018
Google
Received the track bar I ordered, product looks extremely strong, thx core 4x4
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.
DS
Dana Smith Jul 26, 2025
Google
Excellent, strong, and durable products—perfect for both on-road and off-road applications. The customer service is outstanding—friendly, knowledgeable, and extremely helpful with understanding installation and ensuring I got exactly what I needed. I would definitely order again. Top-notch company with high-quality products made right here in the U.S.A.
Review photo 1 Review photo 2 Review photo 3
EA
Eric Ahonen Mar 24, 2021
Google
Awesome control arms! My mechanic said “ your Jeep is pretty much bulletproof now.” And I just got the tier 1 arms! The people at the core 4x4 shop were really nice too. They were running behind on shipping, (which is understandable) so I decided to go pick it up because it was only an hour drive. They gave me a free $60 hardware kit for the inconvenience. Thanks core 4x4! You guys are awesome!!
WT
William Turton Nov 23, 2025
Google
Finally a company with a great product and customer service to match. I changed my order last minute from short arms to long arms. The lift is extremely well built. Korbey was awesome! Highly recommend Core 4x4
CM
Cameron Masters Mar 24, 2023
Google
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.
CL
Colten Lockwood Mar 25, 2019
Google
Recieved warrenty exchanges for my control arms last night couldnt be happier!!! Lets talk about the arms tho! Great quality arms in multiple styles and colors!!! I purchased the teir 3 short arns for my 98 xj. I can say that they setoff nicely so my 35 inch tires do not rub! As long as you can get a photo or video of broken hardware core will take care of you. The body of the arm is bulletproof. However make sure to maintain and grease the joints regularly as with any greaseable joint and they shouldkast forever. I had a few problems arise a year after purchase and after some troubleshooting spence was able to help get me the correct parts to get back on the road. I recommend this setup to any and all jeepers looking to get away from the stock arm setup. Alltogether i am Very happy with the performace of my control arms!!!! Mechanic and bodyman of 12 years and my first choice for quality control arms!!
BS
Bailey Smith Mar 23, 2025
Google
Core 4x4 excels with precision and service and keeps nothing else higher in mind. Everyone I've met at the company is very honest and down to earth, 10/10 would recommend.
MP
matthew patterson May 27, 2025
Google
Ive used core products for my last two jeeps and now my ram. They’re parts are the absolute best quality youll find ANYWHERE. Top quality products and A+ custom service keeps the as my go Roger for any suspension needs.

Specifications

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