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RockJock Rear Coil Springs, JL, 4 dr. (EcoDiesel and 392), 3.5 in. Lift, Pair
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399.00 399.0 USD 399.00

399.00

Not Available For Sale

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Fitment guarantee Ships from Orem, UT 4–8 hr install
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https://dev.core4x4.com/web/image/product.template/24380/image_1920?unique=de245c6

RockJock Rear Coil Springs, JL, 4 dr. (EcoDiesel and 392), 3.5 in. Lift, Pair

RockJock Rear Coil Springs, JL, 4 dr. (EcoDiesel and 392), 3.5 in. Lift, Pair
SKU: RJ-144401-101
Pick your vehicle to confirm fit

399.00 399.0 USD 399.00

399.00

Not Available For Sale

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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

This pair of RockJock rear coil springs will provide 3 1/2 inches of lift in JL Wrangler Unlimited applications that feature the EcoDiesel or 392 Hemi powertrains. 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
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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
0%
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.
Review photo 1 Review photo 2
SA
Samuel “SamDaman904” Anscher Mar 23, 2024
Google
I meant to put this reviewing about a year ago now, but ever since I’ve had the core 4 x 4, upper and lower control arms on my 2017 ram 1500, they have worked flawlessly leave been on many offering chips, and I’ll definitely be buying new accessories from them in the future and their new upper control arms that they’re offering for all of the ram trucks. Fantastic customer service fantastic health very automotive, off-road, friendly, and any aftermarket thing for your truck or SUV that they currently have!
BC
Brad C Mar 24, 2021
Google
Outstanding experience! I asked Core to build me a set of custom control arms that were larger/heavier than they normally build. They gladly accepted the challenge and turned out an expertly crafted and super strong product ahead of schedule. Fit and finish are excellent. Spence and Cameron were a pleasure to work with every step of the way. And all of this for a very reasonable price. I highly recommend these guys!
Review photo 1
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.
KK
Kevin Kinard Oct 24, 2025
Google
Great product, excellent customer service. I mistakingly ordered a track bar for the wrong year model and Korby helped me out by sending me the correct part that I needed no questions asked. I highly recommend.
CL
Cade Leith Mar 23, 2024
Google
Have full upper/lower CA set on both front and rear axles on a 96 ZJ. These are the rubber bushing sets not joint sets. I have beat the hell out it in the Nevada desert for 2 years and has been great. I don’t go fast but I do articulate suspension a lot. Super solid and haven’t any issues. Just inspected the entire set recently due to some banging under it. Turns out the banging is lower rear shock bushings. Inspected each CA along the way nothing. Aside from dirt and obviously winter roads and what not still in excellent condition, bushings are solid like the day they were installed. I’ll add that I’m about tapped on a short arm at 4.25(less with settle) so the front CA’s get beat on just from that, still they’re like new. Paint is great condition, this set is red. I would definitely buy again. Another plus for me, Utah isn’t local necessarily, but it’s nice to support businesses closer to me.
JS
Jon Stempien May 27, 2025
Google
Big thanks to Corby at core 4 x 4 outstanding customer service I like to thank them or 4 x 4 for helping me Well-made product in the United States recommend core 4 x 4 for all jeep Owners that like the four wheel
AH
Abbey Hiett Mar 25, 2019
Google
Company finally made things right
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!
PG
Paul Griffin Feb 21, 2026
Google
Great long arm kit with everything else I needed as well! They worked with me to ensure that I was getting an upgraded components kit just like I wanted. Fast shipping with some of the best packaging that I have ever seen. Nothing was scratched or missing and this kit is even more impressive than the videos or website can show. Powder coating looks great with no issues. I would highly recommend CORE 4x4 to anyone looking for a great quality kit.

Specifications

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