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Jeep Wrangler JK / JKU 07-18 6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit
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1,994.95 1994.95 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
See full timeline
Lifetime warranty Fitment guarantee Ships from Orem, UT 4–8 hr install
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COLOR 12 colors — pick yours
https://core4x4.com/web/image/product.template/1894/image_1920?unique=edc8f61

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

Jeep Wrangler JK / JKU 07-18 6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit
SKU: J-JK-R-LAK4
Pick your vehicle to confirm fit

1,994.95 1994.95 USD 2,099.95

2,099.95

(Save 5%)

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
    Confirm this matches your vehicle. Use Shop by Vehicle to filter correctly.
  • Brand
  • Color
    Powder coat color for control arms and track bars. Does not affect performance.
  • Lift Size
    Choose your current front lift height. Measure from center of wheel to fender if unsure.
  • 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 Dominance

Take your 2007-2018 Jeep Wrangler JK to the next level with the CORE 4X4 JK Rear Long Arm Kit (J-JK-R-LAK4)—a game-changing upgrade designed to enhance articulation, ride quality, axle stability, and durability. This weld-on kit completely redefines your rear suspension geometry, allowing for a longer arc of travel, resulting in smoother suspension movement, better traction, and unmatched off-road capability.

Designed for serious off-roaders, this kit features massively upgraded bracketry, extended-length control arms, and industry-leading materials for a stronger, more controlled, and more capable suspension system. Whether you're tackling extreme rock crawls, desert trails, or rugged terrain, this rear long arm kit provides unparalleled handling and durability.

Key Features and Benefits

  • Optimized Suspension Travel Geometry – The true long arm design extends control arm mounting points for a longer arc of suspension travel, resulting in a smoother ride, better flex, and superior traction across all terrains. Reduces axle steer and bump steer, improving both high-speed stability and low-speed crawling performance.
  • Ultra-Strong 7075 Aluminum Control Arms with ‘Memory’ – Rear Lower and Upper Long Arms are crafted from 2-inch and 1.5-inch 7075 aluminum, balancing lightweight performance and extreme durability. The 'memory' of 7075 aluminum allows the control arms to flex under impact and return to their original shape, preventing permanent bending or deformation. Improves suspension longevity, ensuring consistent geometry and reliability on the toughest trails.
  • Precision-Welded 3/16” Steel Brackets for Maximum Durability – All frame brackets are laser-cut and precision-bent from 3/16” steel, delivering an unbreakable mounting system that eliminates flex and provides rock-solid stability. The rear frame brackets integrate body mount relocation, eliminating interference issues while reinforcing your Jeep’s structure.
  • Weld-On Installation for a Permanent Performance Upgrade – Requires cutting and welding for installation, ensuring a permanent and incredibly strong suspension system. Professional installation is recommended for optimal results.

Recommended Pairing

For a complete long arm suspension solution, pair this Rear Long Arm Kit with our Front Long Arm Kit (J-JK-F-LAK4) to maximize axle control, stability, and articulation across all terrains.

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. After installation, they can be painted or coated as desired.

Proudly Made in the USA

At CORE 4X4, we manufacture our Long Arm Kits in Orem, UT, using only the highest quality American-sourced materials. Our commitment to strict quality control, rigorous testing, and precision engineering ensures 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 JK Rear Long Arm Kit (J-JK-R-LAK4) is the ultimate rear suspension upgrade for Jeep Wrangler JK owners looking to push their off-road performance to new heights. With extended-length control arms, precision-engineered bracketry, and 7075 aluminum’s impact-resistant memory, this kit delivers maximum articulation, axle stability, and durability.

Upgrade your Jeep Wrangler JK today with the CORE 4X4 Rear Long Arm Kit and experience next-level suspension performance and ride quality, whether on the trail or the road!

 

  • Vehicle Fitment: Jeep Wrangler JK 07-18 – This rear long arm kit enhances suspension travel, articulation, and stability, ensuring a smoother ride and more control, even on the toughest trails and rugged terrains.

  • CORE Advantage: The extended control arm design optimizes suspension geometry, creating a longer arc of travel for smoother suspension movement. This reduces axle steer and bump steer while improving traction and off-road performance.

  • Adjustability: Features on-vehicle adjustability, allowing fine-tuning of axle position and alignment. Fine-tuning ensures optimal suspension geometry for 0-6 inches of lift, while also ensuring perfect control under varying terrain and load conditions.

  • Construction: Built from 2” OD 7075 aluminum for rear lower arms and 1.5” OD for upper arms, this kit ensures maximum strength and flexibility. These arms return to their original shape after impacts, maintaining consistent suspension geometry and long-term durability.

  • 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 2007 - 2018

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 JK / JKU (07–18)
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%
8
89Patriot Jan 22, 2026
Google
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.
MN
Mike Nielsen Nov 23, 2025
Google
The customer service is first class. I had an issue with a track bar I installed on my F350. I don’t have any other Core 4x4 parts yet, but with the way I was treated, I know their parts are well done, because they went above and beyond to make sure I was made whole. They wouldn’t be in business if they had to take care of a lot of people like they took care of me. Will definitely be back when it’s time to build the Jeep!
CL
Colten Lockwood Mar 25, 2019
Google
Recieved warrenty exchanges for my control arms last night couldnt be happier!!! Lets talk about the arms tho! Great quality arms in multiple styles and colors!!! I purchased the teir 3 short arns for my 98 xj. I can say that they setoff nicely so my 35 inch tires do not rub! As long as you can get a photo or video of broken hardware core will take care of you. The body of the arm is bulletproof. However make sure to maintain and grease the joints regularly as with any greaseable joint and they shouldkast forever. I had a few problems arise a year after purchase and after some troubleshooting spence was able to help get me the correct parts to get back on the road. I recommend this setup to any and all jeepers looking to get away from the stock arm setup. Alltogether i am Very happy with the performace of my control arms!!!! Mechanic and bodyman of 12 years and my first choice for quality control arms!!
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
TW
Travis Walker Sep 24, 2025
Google
I have nothing but great things to say about this company and their customer service. If you like American made products backed by warranty and amazing customer support, this is the company for you. I have a Lexus GX470 and love their rear control arms.
Review photo 1 Review photo 2
SA
Samuel “SamDaman904” Anscher Mar 23, 2024
Google
I meant to put this reviewing about a year ago now, but ever since I’ve had the core 4 x 4, upper and lower control arms on my 2017 ram 1500, they have worked flawlessly leave been on many offering chips, and I’ll definitely be buying new accessories from them in the future and their new upper control arms that they’re offering for all of the ram trucks. Fantastic customer service fantastic health very automotive, off-road, friendly, and any aftermarket thing for your truck or SUV that they currently have!
L
luke Mar 24, 2021
Google
Excellent quality product and service. My l lower control arms broke and within the same day core 4x4 hooked me up with tier 2 arms and with the color I wanted. My Jeep rides better and has been solid for several months so far. 10/10 would recommend their products to anyone.
LM
Logan Matejek May 27, 2025
Google
The parts are a massive improvement over factory. I accidentally ordered the wrong endlinks and they helped me figure out the correct size and sent me new ones. Definitely an awesome store
K
Korosunagi Jul 26, 2025
Google
I broke a grease fitting off in my end link. I thought I was going to have to buy a new one. Reached out to Core 4x4 and wham! bam! They fixed it and sent it back with 2 day shipping. Got it a day early even. If they couldn't fix it they were going to send me a new one. Now that's customer service! They are now a permanent part of my garage. Thank you Core 4x4!
MR
Melanee Raynes Mar 25, 2019
Google
Awesome product and service! I even got some of their swag because it looked pretty darn good. I will definitely be going back and would suggest this business to others looking for quality control arms. Buy local!

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 JK / JKU (07–18)
Brand CORE 4X4
Note to Core4x4: -
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