Made in USA
Orem, Utah
Lifetime Guarantee
Unconditional
10 Colors
In-house powder coat
Ships in 3 Days
From our UT facility
Fully Adjustable
0-6" of lift
3 X-Series Options
Only Core 4x4
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 |
Select your lift size in Step 1 — the kit ships with the correct geometry for that height. If you’re running a non-standard setup, call us before ordering and we’ll confirm compatibility.
Death wobble is a geometry problem, not just worn parts. Cruise Series corrects caster angle and eliminates the flex points that let shimmy start. Replacing one part at a time delays the fix — this replaces the geometry.
Yes, if you’ve done a lift kit before. Full-day project. Watch the complete JT install walkthrough on our YouTube channel — most owners wrap it in a day. Any off-road shop can run it if you’d rather have it done.
Any non-wear component fails — we replace it. No mileage cap. No maintenance intervals to track. No fine print about voiding if you miss a service. Lifetime means lifetime.
Teraflex’s lifetime warranty voids if you miss a maintenance interval. MetalCloak’s actual parts warranty is 12 months — their “lifetime” language refers to their service program. No conditions here.
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTube
Reviews from Google
5.0
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132 reviews
EC
Eric Cox
Jul 26, 2025
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Prompt, professional, and courteous service! Quality parts and broad assortment of products to suite your 4x4 needs:)
PB
Peter Busack
May 27, 2025
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Purchased a set of Trailing arms for my Ram 1500, quality is first class. I bought the ones with the Jonny Joints for more articulation and it appears from the construction I should get a lifetime of use, Zerk fittings are an added plus. Would defiantly recommend, and the the service team answered all of my questions.
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niceguyr1
Mar 24, 2023
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I purchased upper and lower adjustable arms for my WJ and lowers were missing the spacers. I didn't know until 3 months later when I was installing them. With absolutely zero hassles they quickly sent me the missing spacers. Fantastic product and service! Huge thank you guys for the awesome service and parts!!! Customer service is quickly becoming a lost commodity and you guys gave me hope that it's still alive and well, you just have to buy from the right people... Thanks again for going above and beyond! 👍👍
TM
Tony Moller
Aug 25, 2025
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Awesome parts! Support the older Jeeps! Great customer service.
OJ
Oldgreg jr
Mar 23, 2025
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Good company, they offer well built parts and Great customer service.
I had a couple of hang ups with my control arms that I purchased, they were very easy to work with and found the solution to make them work.
P
Paul
Mar 24, 2023
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I've been having trouble with the track bar (on my 2nd gen Dodge) since I installed the 3rd gen Synergy adapter bracket and a 3rd gen stock bar.. oddly, they call it a '3rd gen bracket' and the stock 3rd gen bar doesn't quite fit, making contact with the bracket. I had attempted to clearance the bracket but it was still making contact and I could feel it over large bumps.
I reached out to a lot of companies, but Core 4x4 offered to make a custom bar for the application with adjustability and dual Johnny joints. The first pass on it didn't work but they sent me out another passenger side end that made it fit incredibly well.
This was all done solely over email/descriptions/pictures/measurements.
Bar is super high quality and heavy duty, made in the US by a family owned company and carries a lifetime warranty. The customer service was responsive and superb, and the price was a lot less than I expected.
RC
Robert C
May 27, 2025
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Fantastic products! Outstanding performance!! Absolutely the best customer service!! You will not be disappointed!
MM
MIKE (Mike the Mechanic)
Jul 26, 2025
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Amazing company and customer service!!!! I messed up on my order and the fixed it immediately. Would definitely recommend them. Can't wait to hit the trails with their product.
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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.
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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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Specifications
| Vehicle | Jeep Wrangler JL / JLU (18–Present) |
| Brand | RockJock |
