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Jeep Wrangler JL / JLU 18+ 6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit
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1,721.96 1721.96 USD 2,099.95

2,099.95

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Order today — ships by Mon, Jun 1
Salt Lake City, UT change
Order by 3:00 PM MT today — we'll start tomorrow
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Lifetime warranty Fitment guarantee Ships from Orem, UT 4–8 hr install
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COLOR 12 colors — pick yours
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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
Pick your vehicle to confirm fit

1,721.96 1721.96 USD 2,099.95

2,099.95

(Save 18%)

COLOR 12 colors
Black Blue Charcoal Green Light Green Orange Purple Red White Yellow Raw Aluminum Custom Color - Other than what is listed above. Extra charge varies. We will reach out after order is placed.

Build Your Kit

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

Select Color to see price and add to cart.

Order today — ships by Mon, Jun 1
Salt Lake City, UT change
Order by 3:00 PM MT today — we'll start tomorrow
See full timeline

Alignment recommended Lifetime warranty on all non-wear items 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

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!


  • 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, our product includes a lifetime warranty on all non-wear items, providing you with confidence and peace of mind in your purchase.

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.

Make Model Submodel Years
Jeep Wrangler 2018 - Present

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

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

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, lift height, and any add-on options, then add to cart. 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

Reviews of Core 4x4

See all on Google
5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
RC
Robert C May 27, 2025
Google
Fantastic products! Outstanding performance!! Absolutely the best customer service!! You will not be disappointed!
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.
JS
Jeffrey Shafer Jan 22, 2026
Google
Exceptional customer service. All my questions were asked in a timely manner and parts were replaced when an error occured. I encourage people to make purchases due to their exceptional quality products, but also because of their customer service. Will make additional purchases in the future.
AP
Ajay Paynter Mar 9, 2026
Google
Great company, who worked with me on shipping parts, to arrive in time for a show, when I explained my concern of possibly not getting the control arms in time. Quality is amazing on the part, affordable price for what you get, and the powdercoat is top notch, not a single issue with this product, would buy again.
JC
John Cutler Oct 24, 2025
Google
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.
Review photo 1 Review photo 2 Review photo 3 Review photo 4
E(
Eric Hernandez (savagefit) May 27, 2025
Google
The whole process was quick and painless. The products are top tier and when I reached out them for package update info, Korby Linscomb was very responsive, and got me the answers I needed the same day. Even when I emailed back to some additional info, he sent what I was looking for that same day. I love core 4x4 and will be giving them my business from now on.
RM
R2d2 Movi78 Feb 21, 2026
Google
I’m extremely impressed with Core 4x4. The quality of their parts is outstanding — everything feels solid, well‑built, and engineered with real attention to detail. Shipping was fast and everything arrived perfectly packaged. Their customer service is just as good as their products: responsive, helpful, and genuinely committed to making sure you get exactly what you need. Overall, a top‑tier experience. I’ll definitely be buying from them again. Specially thank you Mr. Linscomb from Core 4x4. Arturo M.
GK
GLENN KOSZKA Apr 27, 2025
Google
The folks at Core 4X4 are always wonderful to deal with. They explain your options and never pressure or rush things. The quality of the Core Control Arms is top shelf, especially if your goal is to stop wheel hop. I recommend Core 4x4 without reservation ! ! !
HK
Harold Kruder Mar 23, 2024
Google
I needed some parts and had to replace 1 lower control arm and their customer service is great. Helped with answering my questions and got parts shipped quickly.
TM
Tony Moller Aug 25, 2025
Google
Awesome parts! Support the older Jeeps! Great customer service.

Specifications

Color Black, Blue, Charcoal, Green, Light Green, Orange, Purple, Red, White, Yellow, Raw Aluminum, Custom Color - Other than what is listed above. Extra charge varies. We will reach out after order is placed.
Lift Size 6"+, 4" — 6"
Vehicle Jeep Wrangler JL / JLU (18–Present)
Brand CORE 4X4
Note to Core4x4: -
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