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Johnny Joint Kit, TJ/LJ/XJ/MJ Front End Housing, (30 or 44), Greasable 1/2 in. Thru Bolts, Reqs. Welding
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255.00 255.0 USD 255.00

255.00

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Fitment guarantee Ships from Orem, UT 4–8 hr install
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Johnny Joint Kit, TJ/LJ/XJ/MJ Front End Housing, (30 or 44), Greasable 1/2 in. Thru Bolts, Reqs. Welding

Johnny Joint Kit, TJ/LJ/XJ/MJ Front End Housing, (30 or 44), Greasable 1/2 in. Thru Bolts, Reqs. Welding
SKU: CE-9102K1
Pick your vehicle to confirm fit

255.00 255.0 USD 255.00

255.00

Not Available For Sale

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Lifetime warranty Made in USA

Made in USA Orem, Utah
Lifetime Guarantee Unconditional
10 Colors In-house powder coat
Fully Adjustable 0-6" of lift
3 X-Series Options Only Core 4x4

RockJock's Front Axle Housing Johnny Joint Kit for TJ Wrangler, LJ Unlimited, XJ Cherokee, MJ Comanche and ZJ Grand Cherokee vehicles replaces the front differential housing upper control arm bushings Johnny Joint rod ends to get maximum articulation out of your suspension! This kit includes a Johnny Joint insert for gear case ear and installation tool, as well as 1 in. thick flame-cut steel upright for the tube side, with the Johnny Joint already installed. This kit has you cut off the top of the stock bracket that is on the tube and install the new RockJock piece into the existing bracket base. You then weld the RockJock piece to the existing bracket base. This allows for no welding to be done on the tube, resulting in no warpage of the tube.This kit requires cutting and welding equipment for installation!!! NOTES: This kit included larger than stock, 1/2 in. greasable hardware for use in performance applications! Control arm holes will have to be drilled to accept the 1/2 in. bolts. This kit is for use on any factory Dana 30 or 44 differential only!

Make Model Submodel Years
Jeep Cherokee 1984 - 2001
Jeep Comanche 1986 - 1992
Jeep Wrangler 1997 - 2006
Jeep Wrangler 2004 - 2006

Brand RockJock
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Reviews of Core 4x4

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5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
TM
T Mac Mar 23, 2026
Google
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!!!
MM
Mike Martinez Aug 25, 2025
Google
Phenomenal company - very rare to come by in the automotive industry. Also very impressing. Let me start here. I got a set of yellow sway bar end links for my 19 ram DT (new body style) and let me tell you, I’m hooked. For numerous reasons. One the craftsmanship behind the product is unmatched for sure for without breaking the bank. 2ndly, they stand behind their product. Had a very minor issue and it was resolved in a blink of an eye!!! Insane. Just because of what i listed above i will forever spend my money with core 4x4! And i think you should too! I have no affiliation at all with this company besides being a consumer. I will be ordering my yellow UCAs and the rest of my rear suspension from them here shortly! Korby on the other hand. The representative that helped me went above and beyond FAST. I hung up the phone with him, and with in no lie 3 minutes he was calling back with an answer. GREAT GREAT GREAT customer service, Korby you and core 4x4 are what give us hope in the car community! With much love and great health to you all!!
Review photo 1
JW
Jonathan Word Aug 25, 2025
Google
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.
EA
Eric Ahonen Mar 24, 2021
Google
Awesome control arms! My mechanic said “ your Jeep is pretty much bulletproof now.” And I just got the tier 1 arms! The people at the core 4x4 shop were really nice too. They were running behind on shipping, (which is understandable) so I decided to go pick it up because it was only an hour drive. They gave me a free $60 hardware kit for the inconvenience. Thanks core 4x4! You guys are awesome!!
A
Adam Oct 24, 2025
Google
I couldn't have been more excited for the initial unboxing of these new Core 4x4 UCA's! They appear to be so well built and just a true quality product. Installation was a breeze and the initial testing with the forklift appears to have given me some additional flex with less binding on the rest of the components now that the geometry is back properly aligned. Time will tell how they hold up on my near future off-road adventures but I don't have any doubt that they are up to the task!
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LS
Leonard Smith Jan 22, 2026
Google
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.
RG
Robert Van Gorder Apr 27, 2025
Google
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.
BA
bryan angell Jun 26, 2025
Google
First off amazing products. I got a set of adjustable control arms for my XJ and it is so nice to be able to dial in caster and pinion angles. A quick call and I was able to purchase an adjustable track.
Review photo 1
CL
Colten Lockwood Mar 25, 2019
Google
Recieved warrenty exchanges for my control arms last night couldnt be happier!!! Lets talk about the arms tho! Great quality arms in multiple styles and colors!!! I purchased the teir 3 short arns for my 98 xj. I can say that they setoff nicely so my 35 inch tires do not rub! As long as you can get a photo or video of broken hardware core will take care of you. The body of the arm is bulletproof. However make sure to maintain and grease the joints regularly as with any greaseable joint and they shouldkast forever. I had a few problems arise a year after purchase and after some troubleshooting spence was able to help get me the correct parts to get back on the road. I recommend this setup to any and all jeepers looking to get away from the stock arm setup. Alltogether i am Very happy with the performace of my control arms!!!! Mechanic and bodyman of 12 years and my first choice for quality control arms!!
JF
jacob fezza Mar 24, 2022
Google
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

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