Skip to Content
ADD YOUR VEHICLE
Shop
RockJock Rear Coil Springs, JL, 4 dr. (EcoDiesel and 392), 3.5 in. Lift, Pair
Pick your vehicle to confirm fit

399.00 399.0 USD 399.00

399.00

Not Available For Sale

See financing options →

Fitment guarantee Ships from Orem, UT 4–8 hr install
ADD TO CART →
https://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

  • Vehicle
    Confirm this matches your vehicle. Use Shop by Vehicle to filter correctly.
  • Brand

Select Color to see price and add to cart.

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
Google

Reviews of Core 4x4

See all on Google
5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
EL
Eric Labrum May 27, 2025
Google
Best customer service I have ever experienced. They are my go to source do to quality and service
DT
Dean Tk421 Feb 21, 2026
Google
I purchased the Jeep WJ control arms Camp series over a year ago. Very pleased and impressed. Easy installation and solid build. Bracket broke for rear upper control arm, they redesigned it to be more robust and sent me a new one with hardware, honoring their guarantee!
JG
James Griffin Jul 26, 2025
Google
Customer service is top notch. They answered all of my questions and got me my tracking number for my packages. I just received both of them and the quality is next level. You guys are truly awesome.
Review photo 1
GM
George Mar Sep 24, 2025
Google
Great company. Highly satisfied with Core 4x4 customer service. Had some bushings fall apart around 600 miles from home. Called and spoke with Korby Linscomb on Thursday, late in the afternoon. He was able to get my bushings sent across country overnight at a very reasonable rate. Had me up and running by Friday evening with enough time to enjoy the Great Smoky Mountain Jeep Invasion. Thanks Guys!
Review photo 1
MS
Mr. Smith Nov 23, 2025
Google
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!
Review photo 1
CW
Cody Whitlock Sep 24, 2025
Google
10/10 overall experience, shipping, customer service, and such a great product!
Review photo 1
RR
Ryan Rogers Aug 25, 2025
Google
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.
SG
Sal Giordano Sep 24, 2025
Google
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!
OA
Owen Adams Sep 24, 2025
Google
These guys are awesome I messed up my address on my order somehow and they were so so helpful Korby was right there every step to a solution very communicative and respectful I will definitely be ordering parts with them in the future!
MH
mark hinz Mar 2, 2026
Google
Went above and beyond to get the parts we needed to complete our customers build for Moab Easter safari cant thank you enough for all your hard work and efforts Thank you and look forward to working with you in the near future

Specifications

Vehicle Jeep Wrangler JL / JLU (18–Present)
Brand RockJock
ADD YOUR VEHICLE Find exact-fit parts
Find →
Pick your series in 30 seconds.
Find My Series →
30-second quiz
Shop by vehicle
Loading…
UNIVERSAL · FITS ANYTHING
DRIVETRAIN Choose vehicle for fit
Drivetrain Coming Soon Axles · Gearing · Driveshafts