Skip to Content
ADD YOUR VEHICLE
Shop

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
Pick your vehicle to confirm fit

2,099.95 2099.95 USD 2,099.95

2,099.95

See financing options →

Order today — ships within 1–3 business days
Enter ZIP for arrival estimate 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/1896/image_1920?unique=edc8f61

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

2,099.95 2099.95 USD 2,099.95

2,099.95

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 within 1–3 business days
Enter ZIP for arrival estimate 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
Google

Reviews of Core 4x4

See all on Google
5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
MV
Mr. V Mar 24, 2021
Google
Good quality parts, much stronger than stock
OA
Owen Adams Sep 24, 2025
Google
These guys are awesome I messed up my address on my order somehow and they were so so helpful Korby was right there every step to a solution very communicative and respectful I will definitely be ordering parts with them in the future!
GM
George Mar Sep 24, 2025
Google
Great company. Highly satisfied with Core 4x4 customer service. Had some bushings fall apart around 600 miles from home. Called and spoke with Korby Linscomb on Thursday, late in the afternoon. He was able to get my bushings sent across country overnight at a very reasonable rate. Had me up and running by Friday evening with enough time to enjoy the Great Smoky Mountain Jeep Invasion. Thanks Guys!
Review photo 1
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
MS
Mr. Smith Nov 23, 2025
Google
Have yet to get to try them but I bought some upper, and then later , lower control arms for my 03 rubicon. The pricing is very fair, so fair I was hesitant to even purchase. When the product came in I was happily mistaken. These are some beefy units with an incredible warranty! I’m very excited! I went with the “Camp”series as I mostly daily it. I have trouble with the shipping at times when I ordered but Corby is quick to notice things and help communicate the solution. Looking forward to buying more parts!
Review photo 1
RH
Rex Hodges Jun 26, 2025
Google
After ordering an upper and lower adjustable control arm kit manufactured by CORE 4X4 from a jeep parts distributor who's intials are E.T., they came with 3 of the threaded ends missing. After over 2 months of phone calls and emails to this E.T. company nothing was resolved. I finally decided to call CORE 4X4 myself and tell them my dilemma. I spoke with a very personable and professional gentleman named Korby, who is one of CORE 4X4's representatives, after a brief discussion of what I went thru he simply asked me for a picture and some measurements and the items I was missing and asked if I could cover ONLY the cost of shipping and I had my missing parts in exactly 1 weeks time. This company not only builds all it's parts in the U.S.A., they stand behind their products with great customer service and life time warranty. My experience with this company and their Rep Korby was fantastic. I would definitely recommend CORE 4X4 to anyone who needs parts for any 4x4 projects. You just can't beat their quality and service. Rex Hodges Valparaiso, Indiana
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. 👍 …
C
caleb Mar 24, 2022
Google
Absolutely a great company. Ordered rear lower control arms with hardware but when i got it the hardware wasn't there but they sent it out right away and got a free t-shirt! Highly recommend.
MH
mark hinz Mar 2, 2026
Google
Went above and beyond to get the parts we needed to complete our customers build for Moab Easter safari cant thank you enough for all your hard work and efforts Thank you and look forward to working with you in the near future
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

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: -
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