Skip to Content
ADD YOUR VEHICLE
Shop
Johnny Joint Kit, TJ/LJ/XJ/MJ Front End Housing, (30 or 44), Greasable 1/2 in. Thru Bolts, Reqs. Welding
Pick your vehicle to confirm fit

255.00 255.0 USD 255.00

255.00

Not Available For Sale

See financing options →

Fitment guarantee Ships from Orem, UT 4–8 hr install
ADD TO CART →
https://core4x4.com/web/image/product.template/24167/image_1920?unique=de245c6

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

  • Brand

Select Color to see price and add to cart.

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
Google

Reviews of Core 4x4

See all on Google
5.0
132 reviews
5
97%
4
2%
3
0%
2
1%
1
0%
CM
Craig MacIver May 27, 2025
Google
Got the CAMP version of adjustable control arms and track bars for our 03 TJ with a 3” lift and 33x10.5 KO 2’s. Super beefy bars, great fit and adjustability. Friendly advice and support from Korby at CORE 4X4. Good follow up as well. The ride quality is great as well as the handling. I think it all looks pretty good as well.
Review photo 1 Review photo 2 Review photo 3 Review photo 4
LM
Logan Matejek May 27, 2025
Google
The parts are a massive improvement over factory. I accidentally ordered the wrong endlinks and they helped me figure out the correct size and sent me new ones. Definitely an awesome store
RP
Robin Poole Jul 26, 2025
Google
I had several questions before my purchase and Korby helped me with the correct parts to order and recommendations. Outstanding customer service and product knowledge! Can't wait to install them!
RH
Roger Hooks Jun 26, 2025
Google
2018 Ram 2500 Rear Control Arms and Rear track Bar been running for about a year, Great Solid Products and great one on one customer service, same day response with issue resolved! Thanks Korby!
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!!
MP
matthew patterson May 27, 2025
Google
Ive used core products for my last two jeeps and now my ram. They’re parts are the absolute best quality youll find ANYWHERE. Top quality products and A+ custom service keeps the as my go Roger for any suspension needs.
GV
Gil Valk Sep 24, 2025
Google
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!!!
Review photo 1 Review photo 2 Review photo 3 Review photo 4
VK
Victor Keele Sep 24, 2025
Google
Great customer service. I got my front upper and lower control arms and hardware on Friday afternoon. It didn’t come with instructions so I called Core 4X4 and they immediately e mailed me the instructions. Also, the kit I got had the spacers missing so I called. It was late Friday by thus time but they took care of the issue first thing Monday morning and I got the spacers on Tuesday. Great company.
Review photo 1 Review photo 2
D
David Nov 23, 2025
Google
First of I just want to say Great customer service korby Has helped me from the start and has not let me down! Reached out to him again today and he was able to warranty some parts out for me. As far as the quality of the parts.. excellent! The build quality is great. I can definitely tell a Difference from the cheap oem rear control arms to these and the pan hard bar. Color, From what I can tell it’s super durable been through a few mud holes on top of the daily road grime and after a quick wipe they still pop! Overall I recommend. Customer service is everything for me and it’s definitely there at Core 4x4.
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!
Review photo 1 Review photo 2 Review photo 3 Review photo 4

Specifications

Brand RockJock
ADD YOUR VEHICLE Find exact-fit parts
Find →
Pick your series in 30 seconds.
Find My Series →
30-second quiz
Shop by vehicle
Loading…
UNIVERSAL · FITS ANYTHING
DRIVETRAIN Choose vehicle for fit
Drivetrain Coming Soon Axles · Gearing · Driveshafts