Skip to Content
Shop
Will this fit your rig?
SKU: J-JL-R-LAK4

6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit

Jeep Wrangler JL / JLU 18+ 6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit
$1,847.96 $2,099.95 Save $252

$ 1,847.96 1847.96 USD $ 2,099.95

$ 2,099.95

Save $ 251.99

Built to order, usually ships in 1–3 days.
Enter ZIP for arrival estimate Delivery date by ZIP
Order by 3:00 PM MT today — we'll start tomorrow
See full timeline
COLOR Pick yours
100% bolt-on, no welding Made in USA · Orem, Utah You break it, we replace it Joints you rebuild instead of replace
Talk to an Expert: 385-375-2104 ADD TO CART →
https://jerdev.core4x4.com/web/image/product.template/1896/image_1920?unique=95d2d87

6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit

Jeep Wrangler JL / JLU 18+ 6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit
SKU: J-JL-R-LAK4
Will this fit your rig?

COLOR Pick yours

Build Your Kit

  • Vehicle
  • Brand
  • Color
  • Lift Size
  • Note to Core4x4:

$ 1,847.96 1847.96 USD $ 2,099.95

$ 2,099.95

Save $ 251.99

Select Color to see price and add to cart.

100% bolt-on, no welding Made in USA · Orem, Utah You break it, we replace it Joints you rebuild instead of replace
Talk to an Expert: 385-375-2104
Built to order, usually ships in 1–3 days.
Enter ZIP for arrival estimate Delivery date by ZIP
Order by 3:00 PM MT today — we'll start tomorrow
See full timeline
Core 4x4 Manufactured Social 15 Promo Eligible

Alignment recommended You break it, we replace it. Made In USA

Made in USA Orem, Utah
You break it, we replace it Warranty on non-wear items
10 Colors In-house powder coat
Fully Adjustable 0-6" of lift
3 X-Series Options Only Core 4x4

Product Details

Make Model Submodel Years
Jeep Wrangler 2018–Present

  • Vehicle Fitment: Jeep Wrangler JL 18+ – This rear suspension upgrade enhances articulation, axle stability, and overall ride quality, providing superior off-road performance and control across all terrains, whether off-roading or towing.

  • CORE Advantage: The true long arm design optimizes suspension geometry by extending control arm mounting points, increasing the arc of travel, resulting in smoother suspension movement and improved traction across rugged trails and obstacles.

  • Adjustability: On-vehicle adjustability allows for fine-tuning of the suspension geometry, axle alignment, and pinion angle without removal, ensuring perfect axle centering and optimal ride quality for lifts ranging from 0 to 6 inches.

  • Construction: Built from ultra-strong 7075 aluminum (2” OD for lower arms, 1.5” OD for upper arms), these control arms offer a perfect blend of lightweight durability and impact resistance, ensuring consistent geometry and long-term off-road reliability.

  • Two-Stage Powder Coating: Zinc primer base and top coat available in 10 vibrant colors protect against corrosion and allow for personalized styling of your rig.

  • Warranty and Origin: Proudly manufactured in the United States. You break it, we replace it.

Built With

Rear Lower Control Arms Built With 2” 7075 Aluminum Forged Johnny Joints on both adjustable ends with 1.25” x 12 TPI - 2.32” long threads.

Rear Upper Control Arms Built With 1.5” 7075 Aluminum Forged Johnny Joints on both adjustable ends with 1” x 14 TPI - 3.25” long threads.

Construction & Materials

Rear Lower Control Arms Built With 2” 7075 Aluminum Forged Johnny Joints on both adjustable ends with 1.25” x 12 TPI - 2.32” long threads.

Rear Upper Control Arms Built With 1.5” 7075 Aluminum Forged Johnny Joints on both adjustable ends with 1” x 14 TPI - 3.25” long threads.

Vehicle Jeep Wrangler JL / JLU (18–Present)
Brand CORE 4X4
Color Black or Blue or Charcoal or Green or Light Green or Orange or Purple or Red or White or Yellow or Raw Aluminum or Custom Color - Other than what is listed above. Extra charge varies. We will reach out after order is placed.
Lift Size 6"+ or 4" — 6"
Placement on Vehicle Rear Upper, Rear Lower, Rear
Mounting Style Weld-On

Upgrade Your Jeep’s Rear Suspension for Maximum Off-Road Capability

Take your 2018-Present Jeep Wrangler JL to the next level with the CORE 4X4 JL Rear Long Arm Kit (J-JL-R-LAK4)—a game-changing suspension upgrade designed to enhance articulation, rear axle stability, and overall ride quality. This weld-on kit completely transforms your Jeep’s rear suspension geometry, offering a longer arc of travel for smoother suspension movement, increased traction, and superior off-road handling.

Designed for serious off-roaders, this kit features heavy-duty bracketry, extended-length control arms, and industry-leading materials to ensure unparalleled durability, strength, and performance. Whether you're conquering technical rock crawls, rugged trails, or heavy towing applications, this rear long arm kit provides unmatched control and stability.

Key Features and Benefits

  • Optimized Suspension Travel Geometry – The long arm design extends control arm mounting points, providing a longer suspension arc for smoother articulation, better traction, and improved ride quality. Reduces axle steer, ensuring better performance across all terrains.
  • Ultra-Strong 7075 Aluminum Control Arms with ‘Memory’ – Constructed from 2-inch and 1.5-inch 7075 aluminum, these control arms flex upon impact and return to their original shape, ensuring proper suspension geometry and long-term reliability.
  • Precision-Welded 3/16” Steel Brackets for Maximum Durability – All frame brackets are laser-cut and precision-bent from 3/16” steel, creating an unbreakable mounting system that eliminates flex and maximizes rear-end stability.
  • Weld-On Installation for a Permanent Performance Upgrade – This kit requires cutting and welding, ensuring a permanent and incredibly strong suspension system. Professional installation is recommended for best results.

Recommended Pairing

Pair this Rear Long Arm Kit with our Front Long Arm Kit (J-JL-F-LAK4) for a complete suspension transformation and maximum off-road capability.

Two-Stage Powder Coating for Maximum Durability

All control arms undergo a two-stage powder coating process for enhanced corrosion resistance and customization. This process includes:

A zinc primer base coat to prevent rust and extend longevity.

A top coat available in 10 colors to match your Jeep’s aesthetics.

Brackets come raw steel to ensure proper welding and post-installation finishing.

Proudly Made in the USA

Designed and manufactured in Orem, UT, using only the highest quality American-sourced materials. Strict quality control, rigorous testing, and precision engineering ensure every component is built to handle the toughest off-road conditions. By choosing CORE 4X4, you’re supporting American manufacturing and getting an unmatched product that delivers lasting performance.

Final Thoughts

The CORE 4X4 JL Rear Long Arm Kit (J-JL-R-LAK4) is the ultimate rear suspension upgrade for Jeep Wrangler JL owners looking to maximize off-road performance and ride quality. With extended-length control arms, precision-engineered bracketry, and 7075 aluminum’s impact-resistant memory, this kit delivers exceptional articulation, axle stability, and durability.

Upgrade your Jeep Wrangler JL today with the CORE 4X4 Rear Long Arm Kit and experience next-level suspension performance and control—on the trail and the road!


Each rebuild kit includes all necessary components to replace and restore wearable parts.

Use the vehicle selector on our website to shop by your year, make, and model. On product pages, use the kit builder to select your color, series, and any add-on options, then add to cart — you’ll confirm your lift height at checkout. If you need help, call or email our team.

Standard orders typically ship within 1–3 business days of ordering. Custom color orders take approximately 5–10 business days. Because everything is built in-house, we can turn orders quickly even for custom specifications.

You can reach our team through the contact form on our website, or browse to the Contact Us page. Our team is available to answer pre-sale and technical questions before and after your purchase.

Google

Store reviews on Google

See all on Google
5.0
★ ★ ★ ★ ★
132 reviews
5 ★
97%
4 ★
2%
3 ★
0%
2 ★
1%
1 ★
0%
BW
Brian Wadsworth Jun 26, 2025
★ ★ ★ ★ ★ Google
Amazing product! Shipping was quick, packaging was great and support was outstanding!!
JI
Jerome Segura III Jun 26, 2025
★ ★ ★ ★ ★ Google
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. 👍👍
Review photo 1 Review photo 2
CW
Cody Whitlock Sep 24, 2025
★ ★ ★ ★ ★ Google
10/10 overall experience, shipping, customer service, and such a great product!
Review photo 1
B
Ben Mar 24, 2021
★ ★ ★ ★ ★ Google
2001 Wrangler TJ- i have purchased all front/rear upper/lower control arms. Front track bar and rear track bar. Quality is excellent and extremely durable you can tell its built to last. Bent a bolt on the front track bar and called and spoke with Spence. He immediately sent me out new hardware plus some! Product is amazing but what really separates companies apart is their service and these guys are second to none. Thank you all!
BS
Bailey Smith Mar 23, 2025
★ ★ ★ ★ ★ Google
Core 4x4 excels with precision and service and keeps nothing else higher in mind. Everyone I've met at the company is very honest and down to earth, 10/10 would recommend.
MM
MIKE (Mike the Mechanic) Jul 26, 2025
★ ★ ★ ★ ★ Google
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.
AL
Andrew LaFave May 27, 2025
★ ★ ★ ★ ★ Google
I am really please with this company. Great product, i had an issue with a couple of the jonnhy joint bushings, they explained what had caused it and how to fix it. Within hrs of receiving my inquiry, i had heard back with the required info I needed. A couple hrs later problem was fixed and ready for the trail again. They care about heir product and their customers. Thanks crew, you rock
GH
Gary Haag Aug 25, 2025
★ ★ ★ ★ ★ Google
Ordered a set of Core 4x4 control arms for my 2006 Jeep TJ. These are some heavy duty quality control arms. Can't wait to get them installed. Great customer service too!
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!
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
No vehicle selected

Add your vehicle and we'll only show parts that fit it.

Add your vehicle Browse all vehicles
Shop parts
Pick your series in 30 seconds.
Find My Series →
30-second quiz
Shop by Vehicle
Loading…
STEERING
Choose a vehicle to confirm fit
Steering Drag links · Tie rods · Pitman arms · Stabilizers 117 ›
DRIVETRAIN
Choose a vehicle to confirm fit
Drivetrain Axles · Gearing · Driveshafts 1 ›
Made in Orem, UT · You break it, we replace it.
385-375-2104