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
Product Details
This pair of RockJock front coil springs will provide 3 1/2 inches of lift in JL Wrangler Unlimited applications that feature the EcoDiesel, 392 Hemi or 4XE powertrain, as well as JT Gladiators that feature the 3.6L gas engine. These springs directly replace factory springs and are designed to work with RockJock Johnny Joint suspension systems or other manufacturer's lift kits and provide improved ride quality and height control. Finish is gloss black powder coat. Extensive research was done by RockJock to develop the perfect spring rate and quality of the coil springs. The results: they provide the best in comfortable ride and excellent performance off-road. If you need help choosing the correct springs for your Jeep - just call the RockJock sales staff!
| Make | Model | Submodel | Years |
|---|---|---|---|
| Jeep | Wrangler | 2018 - Present |
| Vehicle | Jeep Wrangler JL / JLU (18–Present) |
| Brand | RockJock |
Reviews of Core 4x4
4.8
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161 reviews
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Dastrup Auto
Mar 25, 2019
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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!
AL
Andrew LaFave
May 27, 2025
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I am really please with this company. Great product, i had an issue with a couple of the jonnhy joint bushings, they explained what had caused it and how to fix it. Within hrs of receiving my inquiry, i had heard back with the required info I needed. A couple hrs later problem was fixed and ready for the trail again. They care about heir product and their customers. Thanks crew, you rock
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Zion
Sep 24, 2025
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Every product I have received from them has been nothing short of fantastic. Korby in Customer service went above and beyond to help me fix my own mistake. I cannot reccomend them enough.
MS
Mr. Smith
Nov 23, 2025
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Have yet to get to try them but I bought some upper, and then later , lower control arms for my 03 rubicon. The pricing is very fair, so fair I was hesitant to even purchase. When the product came in I was happily mistaken. These are some beefy units with an incredible warranty! I’m very excited! I went with the “Camp”series as I mostly daily it.
I have trouble with the shipping at times when I ordered but Corby is quick to notice things and help communicate the solution. Looking forward to buying more parts!
AH
Abbey Hiett
Mar 25, 2019
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Company finally made things right
MR
Melanee Raynes
Mar 25, 2019
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Awesome product and service! I even got some of their swag because it looked pretty darn good. I will definitely be going back and would suggest this business to others looking for quality control arms. Buy local!
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.
AM
Adam M
Sep 24, 2025
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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👌🏽
JT
Jay Taylor
May 27, 2025
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Had a worn out set of rear upper control arms on my TJ. These were old rubicon express long arms. can’t buy replacements and no one makes a direct fit replacement.
Talked with Korby at core off road sent some measurements and photos and a week later new arms showed up. Packaging was perfect fit was perfect.
Would highly recommend giving these guys a call.
MP
Mirko Pompili
Mar 19, 2026
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I want to share a truly positive experience.
I ordered a car kit consisting of two packages, but unfortunately one was lost during shipping with UPS. The situation could have become complicated... but it didn't.
The company manager was extremely helpful and professional: he personally followed up on the situation and did everything he could to resolve the issue, even sending me the package again without hesitation.
It's rare to find such attentive and reliable customer service these days.
My sincere congratulations on your professionalism and commitment: that makes all the difference.
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