RockJock Frame Rail Plugs for JK Frame, Front, behind axle centerline, CNC Machined Black Delrin

In September 2025, we visited CORE 4x4 in Orem, Utah. CORE 4x4 makes control arms and other similar parts that stiffen the suspension of an off-road 4x4 vehicles, so that the off-road vehicles can travel on more rugged terrain. CORE 4x4 used to share this building with another business, and since this other business has moved elsewhere, CORE 4x4 will continue to expand and grow their business. Good for CORE 4x4 to be a growing company and to expand into the vacant part of the building.

I recently ordered a set of control arms from Core 4x4, and the entire experience was absolutely top-notch from start to finish. The ordering process was smooth, the parts arrived quickly, and the control arms themselves are extremely high quality—solid construction, great finish, and clearly built to last. I also want to give a special shout-out to Korby, the guy I spoke with during the process. His customer service was amazing. He went above and beyond to make sure I got exactly what I needed, answered all my questions, and made the whole experience stress-free. You don’t see service like that very often these days. If you’re looking for high-quality suspension components backed by truly exceptional customer service, I highly recommend Core 4x4. I’ll definitely be buying from them again.

Beefy parts made and painted well, very fair pricing for what you get, and fantastic customer service to boot. Easily my favorite place to get suspension parts.

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. 👍👍

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.

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.

I purchased a upper and lower set of control arms from core 4x4 they came early then expected and seem to be very nice quality I ran into a complication installing them and emailed them my question I was expecting to get the response maybe the next day because it was after hours I got a response in about a few minutes which allowed me to finish the project that day I super appreciate that, the products are good strong lifetime warranty and their customer service is top notch