Skip to Content
Shop

FITS

2007–18 Jeep Wrangler JK / JKU

SKU: J-JK-R-LAK4

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
$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.
Checking shipping cost… Check shipping
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://dev.core4x4.com/web/image/product.template/1894/image_1920?unique=db5d46b

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
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.
Checking shipping cost… Check shipping
Enter ZIP for arrival estimate Delivery date by ZIP
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
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 2007–2018

  • 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.

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

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!

 

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, 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

Store reviews on Google

See all on Google
5.0
★ ★ ★ ★ ★
132 reviews
5 ★
97%
4 ★
2%
3 ★
0%
2 ★
1%
1 ★
0%
JS
Jon Stempien May 27, 2025
★ ★ ★ ★ ★ Google
Big thanks to Corby at core 4 x 4 outstanding customer service I like to thank them or 4 x 4 for helping me Well-made product in the United States recommend core 4 x 4 for all jeep Owners that like the four wheel
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!
MG
Morgan Griffith Mar 25, 2018
★ ★ ★ ★ ★ Google
I met a couple of the Core 4x4 guys at the Salt Lake Offroad Expo and decided to try them out after noticing one of my control arm bushings was disintegrated. I called to discuss parts on Thursday and I was leaving for a trip on Saturday. These guys built my control arms and had them ready to be picked up Friday, 24 hours later. The parts seem to be great quality and they charged me nothing extra to have them painted. These guys were extremely helpful and without them my trip probably would have been cancelled. looking forward to testing out the arms on my next trip to Moab.
N
Nick Sep 24, 2025
★ ★ ★ ★ ★ Google
I have a 2016 RAM 1500 Crew Cab and I replaced the rear upper and lower control arms also the pan hard track bar and also the sway bar and links for the rear with all I had the articulating bushings. The vehicle now has no body role. They are absolutely incredible if you get the control arms you gotta get the CORE 4 x 4sway bar end links don’t don’t try and be cheap and get Moog or something else you got to get articulating bushings get the core 4 x 4 ones they are the best. My truck drives now through the canyons like a BMW. I have Fox high-performance shocks on there as well with all the CORE 4 x 4 suspension parts and they are amazing. Well worth the money I would highly recommend anybody thinking about CORE 4 x 4 go with CORE 4X4 and if you can go with their articulating bushings, they’re unbelievable drives better now than my Escalades. Well planted no body role and smooth on the Highway unbelievable the difference they all made!! THANKS AGAIN CORE 4x4!!!!
PB
Peter Busack May 27, 2025
★ ★ ★ ★ ★ Google
Purchased a set of Trailing arms for my Ram 1500, quality is first class. I bought the ones with the Jonny Joints for more articulation and it appears from the construction I should get a lifetime of use, Zerk fittings are an added plus. Would defiantly recommend, and the the service team answered all of my questions.
AS
Anthony Snyder Jun 26, 2025
★ ★ ★ ★ ★ Google
Great experience and really great parts
AL
Aaron Lake Apr 27, 2025
★ ★ ★ ★ ★ Google
Korby was a great help with getting me a set of leaf springs for my Cherokee. Great customer service and an awesome product all made in the USA. Proud to support and rock their parts on my vehicle. 👍 …
RC
Ryan Colligan Mar 4, 2026
★ ★ ★ ★ ★ Google
I have nothing but good things to say about Core 4x4. I have the crawler series on my JKU and we take it all over the place. These parts handle everything we throw at them.
CM
Cameron Masters Mar 24, 2023
★ ★ ★ ★ ★ Google
Absolutely incredible family owned business. I asked to pick up my order since I’m local and they came in on a weekend to accommodate. Had to make some adjustments to parts and took the time to make sure it was perfect. Parts are incredible quality. If you have a Jeep, do not hesitate to support this local business.
Z
Zion Sep 24, 2025
★ ★ ★ ★ ★ Google
Every product I have received from them has been nothing short of fantastic. Korby in Customer service went above and beyond to help me fix my own mistake. I cannot reccomend them enough.
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…
DRIVETRAIN
Choose a vehicle to confirm fit
Drivetrain Coming Soon Axles · Gearing · Driveshafts ›
MORE PARTS
Parts & Accessories 813 ›
Made in Orem, UT · You break it, we replace it.
385-375-2104