This pair of RockJock rear coil springs will provide 4 inches JK Wrangler and JK Wrangler Unlimited (2 or 4-door) applications. 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 | 2007 - 2018 |
| Brand | RockJock |
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTubeReviews from Google
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132 reviews
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Ajay Paynter
Mar 4, 2026
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Great company, who worked with me on shipping parts to arrive in time for a show. When I explained my concern they went above and beyond to make it happen. Quality of the parts is top notch.
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Ryan Colligan
Mar 4, 2026
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I have nothing but good things to say about Core 4x4. I have the crawler series on my JKU and we take it all over the place. These parts handle everything we throw at them.
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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.
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89Patriot
Jan 22, 2026
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Great company! I have used there products consistently with no complaints with quality you can see and feel. From my experience, their customer service is also amazing. Core 4x4 has no issues standing behind their already amazing products and will quickly and professionally solve issues may they arise. I will continue to be a customer.
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Noah Myers
Mar 23, 2024
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I contacted these guys on a Saturday through email and needed some control arms by the following weekend, Spence got back with me and told me he would make sure the order got shipped out on Monday, they got busy and wasn’t able to ship the package out so he got back with me that evening and upgraded my shipping for free and shipped out the next day, only because he told me he’d make sure I’d have them by the weekend! This company sticks to their word! The customer service from these guys are unmatched and they will have another lifetime customer here!
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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.
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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!
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John Cutler
Oct 24, 2025
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In September 2025, we visited CORE 4x4 in Orem, Utah. CORE 4x4 makes control arms and other similar parts that stiffen the suspension of an off-road 4x4 vehicles, so that the off-road vehicles can travel on more rugged terrain. CORE 4x4 used to share this building with another business, and since this other business has moved elsewhere, CORE 4x4 will continue to expand and grow their business. Good for CORE 4x4 to be a growing company and to expand into the vacant part of the building.
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Don
Jul 26, 2025
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Great shop, great parts and great service. You want to buy off this company and company’s like this!!!! Wish we had more companies as good as this one!! Thank you
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Ryan Rogers
Aug 25, 2025
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I purchased a set of the Cruiser Series control arms for my Jeep Jk based on postive reviews from different Jeep Facebook pages. Ordered and 2 days later realized they had the very same exact arms on sale in the overstock section. Called them up and they refunded me the savings from my original purchase. Amazing, honest service. Can't wait to get them installed. Keep up the good work guys.