The Special Sauce:
HOUSING
- SAE 1045 Solid Steel Forged Housing: This is unequivocally the best carbon alloy steel for this application.
- Knurled Housings: The preferred design for aftermarket installations.
- CNC Machined Housing: Make our parts and bearings dimensionally perfect, eliminating any die wear issues.
BALL STUDS
- SAE 4140 Hot Forged Chromoly Ball Studs: For the strongest possible metallurgy.
- Induction Heat Treated Ball Studs: Provides a very precise heat treatment to the exact depth and location we want it.
- LOWER: Polished Ball Studs: Built like an anti-friction bearing with extremely precise tolerances.
- Rolled Threads: Made by pressing the shape of the threads into the ball stud instead of cutting. This strengthens the threads instead of weakening them and allows for easy movement of hardware. This ain't no Ikea furniture!
- Step Thread: Allows for very easy movement of hardware on install and superior holding when torqued (installer choice).
BEARING DESIGN
- UPPER: Carbon Bearing Design: Used mainly in Jeep and Dodge upper ball joints is the solver of all things wobbly. Like all our products.
- LOWER: Military Grade Acetal Bearing: The same bearing material spec'd by the US military for Hummer ball joints. This material is: dimensionally stable (doesn't expand or contract with hot or cold, water or oil absorption), can be polished smooth as steel, is anti-friction, doesn't wear itself out under load like metal on metal, and can take an absolute pounding.
BOOTS
- CR Rubber Boots: The most durable material for undercar applications. Resistant to deterioration from road level ozone, oil/gas/engine fluids and extreme heat or cold.
- Pancake Boot
HARDWARE
- Grade 8 - Class 10.9 Hardware: Superior tensile strength.
- Castle Nut: Industry standard where high vibration loads occur.
LUBRICATION
- Pre Threaded Zerk Housing: If you have ever installed a MOOG Ball Joint without a pre-threaded zerk fitting you will understand what a simple but great feature this is. Another installer fav.
- Greaseable: Because it should be.
- Pre-Greased: Just in case you forget, we have you covered.
- Gull Winged Grease Grooves: Allows for improved lubrication disbursement around the ball stud.
- Zerk Fittings: Included for every application.
SPECIAL FEATURES
- Custom Features: UPPER: Custom Bearing design to eliminate Death Wobble.
- Custom Features: LOWER: Angled Zerk housing for easier servicing.
Where It Fits:
Vehicle Position: Front Upper, Front Lower
Quantity per Vehicle: 1
Moog Interchange: K3134T & K3185
XRF Interchange: K3134TX & K3185
| Make | Model | Submodel | Years |
|---|---|---|---|
| Jeep | Grand Cherokee | 1999 - 2004 | |
| Jeep | Wrangler | 2007 - 2018 |
| Brand | Apex Chassis |
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTubeReviews from Google
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132 reviews
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Ajay Paynter
Mar 4, 2026
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Great company, who worked with me on shipping parts to arrive in time for a show. When I explained my concern they went above and beyond to make it happen. Quality of the parts is top notch.
RC
Ryan Colligan
Mar 4, 2026
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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.
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Marcus Torres
Jan 15, 2026
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Best control arms I have installed on any of my builds. After running every major manufacturer, Core 4x4 is on par or better than all the high-end companies at a fraction of the cost. Lifetime warranty is the cherry on top.
OA
Owen Adams
Sep 24, 2025
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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!
FS
Fernando Salazar
Aug 25, 2025
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Great quality control arms and great customer service. Korby has been a great help at answering my questions on some issues I’ve been having with installation!
JT
jacob trice
Apr 27, 2025
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Core 4x4 has outstanding products at a fair price and unmatched customer service. When you call Korby, it's like talking with a friend. Very cool and helpul!
I ordered some custom control arms, but from the wrong product line and they were super cool about returning them and upgrading to a better "Crawl" series. Only charged the difference between the two products. They paid all the return shipping and sent the uprgaded arms super quick. It was only a couple days. Awesome!!
I couldn't be happier with the transaction👍🏼
Also, these control arms are stout and take a beating. I run heck out my Jeep in the rocks and desert. No problems whatsoever.
Thanks Core 4x4, ya'll are welcome at my campfire anytime!
Jake T.
Pleasant Hill, Or.
RH
Roger Hooks
Jun 26, 2025
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2018 Ram 2500 Rear Control Arms and Rear track Bar been running for about a year, Great Solid Products and great one on one customer service, same day response with issue resolved!
Thanks Korby!
TM
T Mac
Mar 23, 2026
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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!!!
TW
Travis Walker
Sep 24, 2025
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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.
MB
Melody Baker
Jan 22, 2026
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I ordered a part for my 03 Jeep TJ and all I can say is wow! Korby at Core 4x4 is a total rockstar!! There was a glitch with my payment and within minutes, Korby reached out to me to get it fixed, then sent my receipt with the tracking number. I lost the number and reached out to him during the Holidays and got a rapid response with the number again. I can’t say enough about the customer service and the quality of parts. Thank you!!