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.
- UPPER: Plunger Design Stud:Unique to Jeep and allows up and down movement with no side-to-side movement.
- 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 Threads: 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), it 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
FINISH
- E-Coating: Extremely durable electrochemical finishing process
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 & K3161T
| Make | Model | Submodel | Years |
|---|---|---|---|
| Jeep | Cherokee | 1984 - 2001 | |
| Jeep | Comanche | 1986 - 1992 | |
| Jeep | Grand Cherokee | 1993 - 1998 | |
| Jeep | Wrangler | 1997 - 2006 | |
| Jeep | Wrangler | 2004 - 2006 |
| 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.
MT
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.
J
Justin
Mar 24, 2021
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Small business, family owned, made in the USA, lifetime warranty. Purchased Tier 3 control arms and rear track bar for a 2006 Jeep LJ. Simple website and easy to contact over phone and email. I had some technical questions and they were happy to answer them. They allow local pickup and were built to order same week. The order was wrapped and ready when I walked in and even gave a tour of the shop. They abrasive blast all raw materials to achieve a better surface profile for powdercoat to adhere and create a smooth, durable finish. I also noticed several CNC machines and a robotic welder they use for all their parts. A small outfit with a robotic welder? Their concern for quality is obvious and it shows in the parts they make. Very impressed. Happy to do business with these guys.
DS
Dana Smith
Jul 26, 2025
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Excellent, strong, and durable products—perfect for both on-road and off-road applications. The customer service is outstanding—friendly, knowledgeable, and extremely helpful with understanding installation and ensuring I got exactly what I needed. I would definitely order again. Top-notch company with high-quality products made right here in the U.S.A.
MH
Matthew Handy
Sep 24, 2025
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Ran into an issue with a part that I ordered. Got ahold of them explained to them the issue I was having and they jumped in and got the issue fixed. Hands down the best customer service I have ever dealt with. The parts are hands down amazing. Highly recommend.
JM
Jason Mitchell
Dec 8, 2025
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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.
TH
Todd Hume
Jan 22, 2026
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Their products are great but the service is even better!! Thanks Korby.
MM
Mike Martinez
Aug 25, 2025
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Phenomenal company - very rare to come by in the automotive industry. Also very impressing. Let me start here. I got a set of yellow sway bar end links for my 19 ram DT (new body style) and let me tell you, I’m hooked. For numerous reasons. One the craftsmanship behind the product is unmatched for sure for without breaking the bank. 2ndly, they stand behind their product. Had a very minor issue and it was resolved in a blink of an eye!!! Insane. Just because of what i listed above i will forever spend my money with core 4x4! And i think you should too! I have no affiliation at all with this company besides being a consumer. I will be ordering my yellow UCAs and the rest of my rear suspension from them here shortly!
Korby on the other hand. The representative that helped me went above and beyond FAST. I hung up the phone with him, and with in no lie 3 minutes he was calling back with an answer. GREAT GREAT GREAT customer service, Korby you and core 4x4 are what give us hope in the car community! With much love and great health to you all!!
K
Korosunagi
Jul 26, 2025
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I broke a grease fitting off in my end link. I thought I was going to have to buy a new one. Reached out to Core 4x4 and wham! bam! They fixed it and sent it back with 2 day shipping. Got it a day early even. If they couldn't fix it they were going to send me a new one. Now that's customer service! They are now a permanent part of my garage.
Thank you Core 4x4!