Made in USA
Orem, Utah
Lifetime Guarantee
Unconditional
10 Colors
In-house powder coat
Ships in 3 Days
From our UT facility
Fully Adjustable
0-6" of lift
3 X-Series Options
Only Core 4x4
RockJock's forged Johnny Joints for fabricators and suspension system builders offer 30 degrees of unrestricted movement in any direction as compared to 22 degrees on a common heim joint! Johnny Joint rod ends offer cushioning that a heim joint cannot provide via high-density urethane bushings that encase the inner ball. The heat treated center balls are cross-drilled for thru-bolt lubrication and the joint internals are retained with 2 heavy duty, heat treated side washers and a snap ring. This specific joint is designed to fit the frame side of the 2021 and up Bronco's rear control arms and feature a 2 1/2 in. diameter joint body, fitted with a zerk fitting for greasing, 2.3 in. of 1 1/4 in.-12 right hand threads on the shank, and a 3.150 in. mounting width ball with a .718 in. thru hole. Finished in gold zinc plating.RockJock's forged Johnny Joints for fabricators and suspension system builders offer 30 degrees of unrestricted movement in any direction as compared to 22 degrees on a common heim joint! Johnny Joint rod ends offer cushioning that a heim joint cannot provide via high-density urethane bushings that encase the inner ball. The heat treated center balls are cross-drilled for thru-bolt lubrication and the joint internals are retained with 2 heavy duty, heat treated side washers and a snap ring. This specific joint is designed to fit the frame side of the 2021 and up Bronco's rear control arms and feature a 2 1/2 in. diameter joint body, fitted with a zerk fitting for greasing, 2.3 in. of 1 1/4 in.-12 right hand threads on the shank, and a 3.150 in. mounting width ball with a .718 in. thru hole. Finished in gold zinc plating.
| Brand | RockJock |
Select your lift size in Step 1 — the kit ships with the correct geometry for that height. If you’re running a non-standard setup, call us before ordering and we’ll confirm compatibility.
Death wobble is a geometry problem, not just worn parts. Cruise Series corrects caster angle and eliminates the flex points that let shimmy start. Replacing one part at a time delays the fix — this replaces the geometry.
Yes, if you’ve done a lift kit before. Full-day project. Watch the complete JT install walkthrough on our YouTube channel — most owners wrap it in a day. Any off-road shop can run it if you’d rather have it done.
Any non-wear component fails — we replace it. No mileage cap. No maintenance intervals to track. No fine print about voiding if you miss a service. Lifetime means lifetime.
Teraflex’s lifetime warranty voids if you miss a maintenance interval. MetalCloak’s actual parts warranty is 12 months — their “lifetime” language refers to their service program. No conditions here.
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTubeReviews from Google
5.0
★
★
★
★
★
132 reviews
BC
Brad C
Mar 24, 2021
★
★
★
★
★
Outstanding experience! I asked Core to build me a set of custom control arms that were larger/heavier than they normally build. They gladly accepted the challenge and turned out an expertly crafted and super strong product ahead of schedule. Fit and finish are excellent. Spence and Cameron were a pleasure to work with every step of the way. And all of this for a very reasonable price. I highly recommend these guys!
MT
Ma TheMeatLoaf
Mar 23, 2024
★
★
★
★
★
Their website estimated 2 days to get my parts but actually took 11. No communication to let me know what’s going on. Parts were missing. Some days they answer questions, some they don’t. Didn’t let me know I’d have to alter stock bolts to fit their parts.
All around just seems like they don’t care.
RC
Ryan Colligan
Mar 4, 2026
★
★
★
★
★
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.
TM
T Mac
Mar 23, 2026
★
★
★
★
★
CORE 4X4 Company produces/manufactures exceptional products. My rear upper and lower control arms and rear track bar were powder coated custom Fox “Shock Orange” for my 2024 Bronco Wildtrak. OEM looks minimal compared to the CORE 4X4 control arms. Plus they’re adjustable, serviceable and rebuildable. Shipment was very fast and packaging used custom foam wrapped around the arms and heavy duty boxes. Not even UPS could damage. Korby L. was great to work with and responded quickly with emails and product information. Great products. Great people from the State of Utah. All Made in the USA. 5 Stars!!!
OK
oleg k
Nov 23, 2025
★
★
★
★
★
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.
NP
Norb Pranger
Oct 24, 2025
★
★
★
★
★
Not sure where to start, Products or Service or Warranty.
Products: I found Core4x4 through a very respected YouTuber in the Jeeping community. I purchased an entire set of Core4x4 Control Arms three years ago and have beat the daylights out of them and they are still in great condition. Now, I purchased another Jeep, this time for my daughter and bought yet another set of Control Arms because I know that these things can take a beating and stand up to it. I plan on replacing more parts on this TJ and my JL and will continue to buy from Core4x4.
Service: This isn't some huge name conglomerate that treats you like you're just another customer. They are quick with responses and will always make things right should something be a problem. Oh and the quickness in which they ship their products is unmatched. I bought these CAs for my TJ on Thursday, I received them on Monday. Most other manufacturers will tell you weeks, they had them to me in 2 shipping days.
Warranty: Seriously, a lifetime warranty? Yes please. Nothing more to say.
I can't say enough about how great of a company this is. I've even spoken to the owner through email a few years back on some questions that I had. Support small American built businesses.
P.S. Core 4x4, feel free to make me an ambassador and send me some swag :) .
FS
Fernando Salazar
Aug 25, 2025
★
★
★
★
★
Great quality control arms and great customer service. Korby has been a great help at answering my questions on some issues I’ve been having with installation!
MM
MIKE (Mike the Mechanic)
Jul 26, 2025
★
★
★
★
★
Amazing company and customer service!!!! I messed up on my order and the fixed it immediately. Would definitely recommend them. Can't wait to hit the trails with their product.
CL
Cade Leith
Mar 23, 2024
★
★
★
★
★
Have full upper/lower CA set on both front and rear axles on a 96 ZJ. These are the rubber bushing sets not joint sets. I have beat the hell out it in the Nevada desert for 2 years and has been great. I don’t go fast but I do articulate suspension a lot. Super solid and haven’t any issues. Just inspected the entire set recently due to some banging under it. Turns out the banging is lower rear shock bushings. Inspected each CA along the way nothing. Aside from dirt and obviously winter roads and what not still in excellent condition, bushings are solid like the day they were installed. I’ll add that I’m about tapped on a short arm at 4.25(less with settle) so the front CA’s get beat on just from that, still they’re like new. Paint is great condition, this set is red. I would definitely buy again. Another plus for me, Utah isn’t local necessarily, but it’s nice to support businesses closer to me.
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.
Your Dynamic Snippet will be displayed here...
This message is displayed because youy did not provide both a filter and a template to use.
Specifications
| Brand | RockJock |