Made in USA
Orem, Utah
You break it, we replace it
Warranty on non-wear items
10 Colors
In-house powder coat
Fully Adjustable
0-6" of lift
3 X-Series Options
Only Core 4x4
Product Details
| Brand | RockJock |
RockJock's custom, small hex 1 in.-14 RH thread Jam Nut features a smaller hex size than standard Jam Nuts, allowing it to tuck into tighter places in brackets, etc. This nut is a 1 3/8 in. wrench size, as opposed to a 1 1/2 in. wrench size of a standard 1 in. thread Jam Nut. Nut is finished in gold zinc plating.
Store reviews on Google
5.0
★
★
★
★
★
132 reviews
LS
Leonard Smith
Jan 22, 2026
★
★
★
★
★
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.
AS
Anthony Snyder
Jun 26, 2025
★
★
★
★
★
Great experience and really great parts
MH
mark hinz
Mar 2, 2026
★
★
★
★
★
Went above and beyond to get the parts we needed to complete our customers build for Moab Easter safari cant thank you enough for all your hard work and efforts
Thank you and look forward to working with you in the near future
RG
Robert Van Gorder
Apr 27, 2025
★
★
★
★
★
Amazing service. Bought a track bar through Americantrucks.com and they sent it with the wrong size bushing sleeve. Korby at Core 4x4 was quick to get me the correct size and very responsive. Will definitely be using more of their stuff.
RM
R2d2 Movi78
Feb 21, 2026
★
★
★
★
★
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.
CM
Cameron Masters
Mar 24, 2023
★
★
★
★
★
Absolutely incredible family owned business. I asked to pick up my order since I’m local and they came in on a weekend to accommodate. Had to make some adjustments to parts and took the time to make sure it was perfect. Parts are incredible quality. If you have a Jeep, do not hesitate to support this local business.
BS
Bailey Smith
Mar 23, 2025
★
★
★
★
★
Core 4x4 excels with precision and service and keeps nothing else higher in mind. Everyone I've met at the company is very honest and down to earth, 10/10 would recommend.
GV
Gil Valk
Sep 24, 2025
★
★
★
★
★
Excellent service, Prompt responses when needing technical assistance, Amazing looking parts that fit excellently. I would recommend them to anyone looking for suspension components. Also very well packaged when we received the shipment, which means no damage from shipping company!! We went with the Crawl Series double adjustable kit and it definitely looks killer on our build!!!
DW
Darin Wuebbels
May 27, 2025
★
★
★
★
★
Thanks for the fabulous customer service. Your products and customer service are first class. I highly recommend these guys. Excellent experience.
AL
Aaron Lake
Apr 27, 2025
★
★
★
★
★
Korby was a great help with getting me a set of leaf springs for my Cherokee. Great customer service and an awesome product all made in the USA. Proud to support and rock their parts on my vehicle. 👍 …
Your Dynamic Snippet will be displayed here...
This message is displayed because youy did not provide both a filter and a template to use.