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: Dual 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
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 & 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.
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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.
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89Patriot
Jan 22, 2026
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Great company! I have used there products consistently with no complaints with quality you can see and feel. From my experience, their customer service is also amazing. Core 4x4 has no issues standing behind their already amazing products and will quickly and professionally solve issues may they arise. I will continue to be a customer.
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!
DW
Derek Whitfield
Nov 20, 2025
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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.
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jacob fezza
Mar 24, 2022
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I wanted to take a moment and give these guys a shout out, I’ve currently got, for my xj, their adjustable control arms, tier 4 adjustable track bar and adjustable leaf spring shackles. You can always count on a fair price, high quality products, and quick delivery. Keep up the great work guys, will definitely continue to shop with you
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!
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Ben
Mar 24, 2021
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2001 Wrangler TJ- i have purchased all front/rear upper/lower control arms. Front track bar and rear track bar. Quality is excellent and extremely durable you can tell its built to last. Bent a bolt on the front track bar and called and spoke with Spence. He immediately sent me out new hardware plus some! Product is amazing but what really separates companies apart is their service and these guys are second to none. Thank you all!
DW
Darin Wuebbels
May 27, 2025
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Thanks for the fabulous customer service. Your products and customer service are first class. I highly recommend these guys. Excellent experience.