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Master Rebuild kit for CRL-J-JL-RTB1
SKU: CRL-J-JL-RTB1-MRK ★★★★★ (132 reviews)
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42.00 42.0 USD 42.00

42.00

Not Available For Sale

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Fitment guarantee Ships from Orem, UT 4–8 hr install
https://core4x4.com/web/image/product.template/27126/image_1920?unique=2d5d26f

Master Rebuild kit for CRL-J-JL-RTB1

Master Rebuild kit for CRL-J-JL-RTB1
SKU: CRL-J-JL-RTB1-MRK
Pick your vehicle to confirm fit

42.00 42.0 USD 42.00

42.00

Not Available For Sale

Compare all tiers →

Select Color to see price and add to cart.

Lifetime warranty on all non-wear items United States

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

Everything you need to refresh your suspension.

This rebuild kit includes all the essential components needed to replace common wear items and restore performance.

CE-9112NRK × 2

Make Model Submodel Years
Jeep Wrangler 2018 - Present

Construction & Materials

Jeep Wrangler JL / JLU 18+ Crawl Series Rear Heavy-Duty Adjustable Track Bar

Rear Track Bar built with 1.5” OD 5/16” Wall DOM. Welded Johnny Joint on the fixed end and a Forged Johnny Joints on the adjustable end with 1” x 14 TPI - 2.32” long threads.

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Reviews of Core 4x4

See all on Google
5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
S
Sebastian Oct 24, 2025
Google
Great products they sell, got a crawl series long arm kit for my xj and it has held up quite nice, they are beefy, and for what ever reason they fail it has a great warranty with a customer service to match, when someone asks what control arm kit to buy I always recommend core 4x4
P
Paul Mar 24, 2023
Google
I've been having trouble with the track bar (on my 2nd gen Dodge) since I installed the 3rd gen Synergy adapter bracket and a 3rd gen stock bar.. oddly, they call it a '3rd gen bracket' and the stock 3rd gen bar doesn't quite fit, making contact with the bracket. I had attempted to clearance the bracket but it was still making contact and I could feel it over large bumps. I reached out to a lot of companies, but Core 4x4 offered to make a custom bar for the application with adjustability and dual Johnny joints. The first pass on it didn't work but they sent me out another passenger side end that made it fit incredibly well. This was all done solely over email/descriptions/pictures/measurements. Bar is super high quality and heavy duty, made in the US by a family owned company and carries a lifetime warranty. The customer service was responsive and superb, and the price was a lot less than I expected.
BB
Brayden Brockey Mar 23, 2024
Google
Got a set of upper control arms for my xj, really impressed with the quality
Review photo 1
CD
Christopher Dami Jun 26, 2025
Google
2022 I ordered a 2023 Jeep Wrangler Rubicon in High Velocity yellow. Without any hesitation I knew I was going with Core 4x4’s 16pc Camp series suspension, powder coated in yellow. Compliments were a given from any and everyone that looked under my jeep. So beefy, I may have left some yellow paint on the rocks from Maine to Florida, but no bends or breaks. Customer service has been perfect each and every time I have needed something. Their warranty is top notch! Their communication is also wonderful. Might upgrade to the Crawl Series control arms where the Johnny joints are on both sides. Great all around company and a great team to troubleshoot your issue and come to a conclusion. Nothing bad to say about this company. Just love this suspension.
Review photo 1 Review photo 2 Review photo 3
NM
Noah Myers Mar 23, 2024
Google
I contacted these guys on a Saturday through email and needed some control arms by the following weekend, Spence got back with me and told me he would make sure the order got shipped out on Monday, they got busy and wasn’t able to ship the package out so he got back with me that evening and upgraded my shipping for free and shipped out the next day, only because he told me he’d make sure I’d have them by the weekend! This company sticks to their word! The customer service from these guys are unmatched and they will have another lifetime customer here!
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.
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!
TM
T Mac Mar 23, 2026
Google
CORE 4X4 Company produces/manufactures exceptional products. My rear upper and lower control arms and rear track bar were powder coated custom Fox “Shock Orange” for my 2024 Bronco Wildtrak. OEM looks minimal compared to the CORE 4X4 control arms. Plus they’re adjustable, serviceable and rebuildable. Shipment was very fast and packaging used custom foam wrapped around the arms and heavy duty boxes. Not even UPS could damage. Korby L. was great to work with and responded quickly with emails and product information. Great products. Great people from the State of Utah. All Made in the USA. 5 Stars!!!
ST
Sal Torres May 27, 2025
Google
upper control arms look great and went on easy.. only reason I gave 4 stars and not 5 is because of a shipping issue which put my build a week behind. The issue was resolved quickly and painlessly, great customer service. Only time will tell how control arms perform but they look great and like they will go above and beyond control arm demand.
SG
Sal Giordano Sep 24, 2025
Google
I want to take the time to share my experience with Core 4x4. I have a 2004 Jeep Wrangler and was looking to upgrade some suspension parts. I went with Core 4x4 upper & lower adjustable control arms and a front adjustable track bar. Everything arrived quickly, and right out of the box I was impressed with the quality and craftsmanship. I had a few questions during installation (measurements and torque specs), and I spoke with Korby on a couple of occasions. Not only did he send me detailed instructions, but he also shared an installation video specific to the part and vehicle I was working on, something you don’t get from many companies. The control arms fit perfectly, look great, and perform exactly as I hoped. I did run into an issue with the front track bar touching the front diff. When I reached out, Korby had me send pictures and then immediately offered two solutions: his bar guy could make a different bend and send it out to me, or I could get a full refund. His response honestly blew me away. As much as I wanted to run the Core 4x4 track bar, I chose the refund. Korby sent me a prepaid shipping label right away, no hassle. My experience with Core 4x4 has been excellent. Korby was extremely understanding, communicative, and helpful every step of the way. The parts I received were high quality, and the customer service was second to none. I would absolutely recommend Core 4x4 10 out of 10 times and will be using them again. Just a great American company with awesome people who truly care about their customers. Thank you Korby, and thank you Core 4x4!
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