Master Rebuild kit for CMP-J-ZJ-RS4

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.

I don’t write reviews often, but Core 4x4 absolutely earned this one. I recently ordered leaf spring mounts and realized after the fact that I messed up my order. Totally my mistake. Instead of giving me the runaround or pointing at a return policy, Core 4x4 emailed me back and forth, worked through exactly what I was doing with my build, and made sure I ended up with the correct parts. That kind of customer service is rare these days — especially in the off-road world where a lot of companies stop caring once the order is placed. The parts themselves are exactly what you hope for: solid, well-made, confidence-inspiring hardware that looks like it belongs under a vehicle that actually gets used. You can tell these are designed by people who understand suspension geometry and real-world abuse, not just CAD screenshots. Mistakes happen — especially on custom or modified builds — and Core 4x4 handled mine like pros. Fast responses, clear communication, and a genuine effort to help me get it right. If you’re on the fence: don’t be. Core 4x4 is the kind of company you want backing your build — the kind that treats customers like fellow enthusiasts, not order numbers.

I’m extremely impressed with Core 4x4. The quality of their parts is outstanding — everything feels solid, well‑built, and engineered with real attention to detail. Shipping was fast and everything arrived perfectly packaged. Their customer service is just as good as their products: responsive, helpful, and genuinely committed to making sure you get exactly what you need. Overall, a top‑tier experience. I’ll definitely be buying from them again. Specially thank you Mr. Linscomb from Core 4x4. Arturo M.

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.

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.

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.

Great products, shipped the next day during a big sale event. Core 4x4 gets it right and gets it done! Thank you all.