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 a TJ Wrangler, or 3 inches of lift in an LJ Unlimited. 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 | 1997 - 2006 | |
| Jeep | Wrangler | 2004 - 2006 |
| Brand | RockJock |
Reviews of Core 4x4
5.0
★
★
★
★
★
132 reviews
NP
Norb Pranger
Oct 24, 2025
★
★
★
★
★
Not sure where to start, Products or Service or Warranty.
Products: I found Core4x4 through a very respected YouTuber in the Jeeping community. I purchased an entire set of Core4x4 Control Arms three years ago and have beat the daylights out of them and they are still in great condition. Now, I purchased another Jeep, this time for my daughter and bought yet another set of Control Arms because I know that these things can take a beating and stand up to it. I plan on replacing more parts on this TJ and my JL and will continue to buy from Core4x4.
Service: This isn't some huge name conglomerate that treats you like you're just another customer. They are quick with responses and will always make things right should something be a problem. Oh and the quickness in which they ship their products is unmatched. I bought these CAs for my TJ on Thursday, I received them on Monday. Most other manufacturers will tell you weeks, they had them to me in 2 shipping days.
Warranty: Seriously, a lifetime warranty? Yes please. Nothing more to say.
I can't say enough about how great of a company this is. I've even spoken to the owner through email a few years back on some questions that I had. Support small American built businesses.
P.S. Core 4x4, feel free to make me an ambassador and send me some swag :) .
D
Danny
Oct 24, 2025
★
★
★
★
★
Outstanding customer service to match the high quality parts. This is the go-to company.
SH
Shawn Hooten
Apr 27, 2025
★
★
★
★
★
Great products, shipped the next day during a big sale event. Core 4x4 gets it right and gets it done! Thank you all.
JJ
JT JT
Dec 23, 2025
★
★
★
★
★
We have all shopped places where the person on the phone makes you feel like they don't have the time to talk to you the customer or answer your questions. I can tell you first hand that's not Core 4x4. They have the best customer service I have seen so far. They have taken the time to respond to all of my questions in a very prompt and professional manner, taking the time to answer each and every question I have had. Lets put it this way if Core 4x4 sells a product I am wanting for my truck I will buy it from them, I highly recommend Core 4x4.
RP
Robin Poole
Jul 26, 2025
★
★
★
★
★
I had several questions before my purchase and Korby helped me with the correct parts to order and recommendations. Outstanding customer service and product knowledge! Can't wait to install them!
JO
Jaime Overmyer
Nov 23, 2025
★
★
★
★
★
Korby was extremely helpful in helping me find the right part for my truck. He was kind, knowledgeable, and patient while I asked a million questions. He also went out of his way to find the right shipping option for me since it’s tricky where I live. I’m looking forward to getting the parts so I can fix my truck and go adventuring again soon!
GC
Grant Chaisson
Jun 26, 2025
★
★
★
★
★
These guys are awesome!! They have helped me build multiple jeeps from zjs to mjs and now with my lj build they all ways impress.
There products are the best on the market in my eyes. The best part about it all is it's all made right here in american and shipped anywhere in the world 🌎 .
Don't think twice when your looking for control arm or lift kits for your vehicle if these guys sell it BUY IT!!!
MM
MIKE (Mike the Mechanic)
Jul 26, 2025
★
★
★
★
★
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.
SG
Sal Giordano
Sep 24, 2025
★
★
★
★
★
I want to take the time to share my experience with Core 4x4.
I have a 2004 Jeep Wrangler and was looking to upgrade some suspension parts. I went with Core 4x4 upper & lower adjustable control arms and a front adjustable track bar. Everything arrived quickly, and right out of the box I was impressed with the quality and craftsmanship.
I had a few questions during installation (measurements and torque specs), and I spoke with Korby on a couple of occasions. Not only did he send me detailed instructions, but he also shared an installation video specific to the part and vehicle I was working on, something you don’t get from many companies.
The control arms fit perfectly, look great, and perform exactly as I hoped. I did run into an issue with the front track bar touching the front diff. When I reached out, Korby had me send pictures and then immediately offered two solutions: his bar guy could make a different bend and send it out to me, or I could get a full refund. His response honestly blew me away. As much as I wanted to run the Core 4x4 track bar, I chose the refund. Korby sent me a prepaid shipping label right away, no hassle.
My experience with Core 4x4 has been excellent. Korby was extremely understanding, communicative, and helpful every step of the way. The parts I received were high quality, and the customer service was second to none.
I would absolutely recommend Core 4x4 10 out of 10 times and will be using them again. Just a great American company with awesome people who truly care about their customers.
Thank you Korby, and thank you Core 4x4!
JI
Jerome Segura III
Jun 26, 2025
★
★
★
★
★
I bought the 16pc Cruise Series Adjustable Control Arm, Track Bar, Steering, End Link Kit to replace a worn budget 4" lift on my used JKU. These are top quality parts; very solid. Customer service is unsurpassed. They even matched prices on my order placed before the tax day sale. I made an error in ordering a drag link flip kit; they were quick to help me fix this too. There's peace of mind knowing these components are made in the USA. Thank you. 👍👍
Your Dynamic Snippet will be displayed here...
This message is displayed because youy did not provide both a filter and a template to use.
Specifications
| Brand | RockJock |