Skip to Content
ADD YOUR VEHICLE
Shop
Jeep Wrangler JK / JKU 07-18 6pc Rear Adjustable Heavy-Duty Kit Long Arm Upgrade Kit
Pick your vehicle to confirm fit

1,994.95 1994.95 USD 2,099.95

2,099.95

(Save 5%)

See financing options →

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
ADD TO CART →
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%
CL
Cade Leith Mar 23, 2024
Google
Have full upper/lower CA set on both front and rear axles on a 96 ZJ. These are the rubber bushing sets not joint sets. I have beat the hell out it in the Nevada desert for 2 years and has been great. I don’t go fast but I do articulate suspension a lot. Super solid and haven’t any issues. Just inspected the entire set recently due to some banging under it. Turns out the banging is lower rear shock bushings. Inspected each CA along the way nothing. Aside from dirt and obviously winter roads and what not still in excellent condition, bushings are solid like the day they were installed. I’ll add that I’m about tapped on a short arm at 4.25(less with settle) so the front CA’s get beat on just from that, still they’re like new. Paint is great condition, this set is red. I would definitely buy again. Another plus for me, Utah isn’t local necessarily, but it’s nice to support businesses closer to me.
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. 👍 …
JM
Jason Mitchell Dec 8, 2025
Google
Installed the full kit on my XJ. Ride quality is night and day better than what I had before. The articulation on the trail is insane. These guys know what they are doing. Already recommended Core 4x4 to everyone in my club.
JJ
JT JT Dec 23, 2025
Google
We have all shopped places where the person on the phone makes you feel like they don't have the time to talk to you the customer or answer your questions. I can tell you first hand that's not Core 4x4. They have the best customer service I have seen so far. They have taken the time to respond to all of my questions in a very prompt and professional manner, taking the time to answer each and every question I have had. Lets put it this way if Core 4x4 sells a product I am wanting for my truck I will buy it from them, I highly recommend Core 4x4.
DW
Derek Whitfield Nov 20, 2025
Google
Solid product, the lifetime warranty sealed the deal for me. Installed on my TJ and the ride quality improved noticeably. Shipping took a bit longer than expected but the parts were worth the wait.
JM
Jay Miller Jul 26, 2025
Google
I purchased a upper and lower set of control arms from core 4x4 they came early then expected and seem to be very nice quality I ran into a complication installing them and emailed them my question I was expecting to get the response maybe the next day because it was after hours I got a response in about a few minutes which allowed me to finish the project that day I super appreciate that, the products are good strong lifetime warranty and their customer service is top notch
BZ
Brandon Zeiders Dec 23, 2025
Google
I ordered the jeep xj long arm lift kit. Control arms showed up first they turned out amazing!! Had some issues with the powder coating on the cross member and sent korby and the team at core4x4 an email. They got right on making me another cross member and sending it out. I appreciate all the help they've given me along the way. Very fast response thru emails. Build quality seems to be pretty dang nice!! Can't wait to install it and enjoy it!
RT
Ruby Timm Apr 27, 2025
Google
Bought a new 2019 Ram 1500. Had bad rear wheel hop since new, got all four core 4x4 control arms and it fixed the issue. Thanks
JH
Joe Hu Sep 24, 2025
Google
Amazing! I put all my new control arms and it drives a lot smoother and looks great!!!
Review photo 1
D
Don Jul 26, 2025
Google
Great shop, great parts and great service. You want to buy off this company and company’s like this!!!! Wish we had more companies as good as this one!! Thank you

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: -
Tags
Tags
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