JKS Greasable Heavy Duty Boomerang Rear Shackles for XJ Cherokees and MJ Comanches have been a staple of the off-roading and desert racing world for decades! Boomerang shackles, due to their unique shape, allow the leaf spring eye to travel dramatically farther up and around the back of the vehicle in extreme articulation conditions, resulting in full compression and extension of the leaf springs. No matter the type of off-roading you are doing, your XJ or MJ's stock shackles and bushings are surely not up to the task. These heavy duty shackles from JKS an extremely strong, fabricated steel design that are up to the task of off-roading or desert racing. Dura-Thane bushings are greasable thru the zerk fitting on the shackle to provide long life and quiet operation.
| Brand | JKS |
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTube
Reviews from Google
5.0
★
★
★
★
★
132 reviews
AP
Ajay Paynter
Mar 4, 2026
★
★
★
★
★
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.
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.
MT
Marcus Torres
Jan 15, 2026
★
★
★
★
★
Best control arms I have installed on any of my builds. After running every major manufacturer, Core 4x4 is on par or better than all the high-end companies at a fraction of the cost. Lifetime warranty is the cherry on top.
DT
Dean Tk421
Feb 21, 2026
★
★
★
★
★
I purchased the Jeep WJ control arms Camp series over a year ago. Very pleased and impressed. Easy installation and solid build. Bracket broke for rear upper control arm, they redesigned it to be more robust and sent me a new one with hardware, honoring their guarantee!
A
Adam
Oct 24, 2025
★
★
★
★
★
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!
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!
WT
William Turton
Nov 23, 2025
★
★
★
★
★
Finally a company with a great product and customer service to match. I changed my order last minute from short arms to long arms. The lift is extremely well built. Korbey was awesome! Highly
recommend Core 4x4
MV
Mr. V
Mar 24, 2021
★
★
★
★
★
Good quality parts, much stronger than stock
GM
George Mar
Sep 24, 2025
★
★
★
★
★
Great company. Highly satisfied with Core 4x4 customer service. Had some bushings fall apart around 600 miles from home. Called and spoke with Korby Linscomb on Thursday, late in the afternoon. He was able to get my bushings sent across country overnight at a very reasonable rate. Had me up and running by Friday evening with enough time to enjoy the Great Smoky Mountain Jeep Invasion. Thanks Guys!
JF
jacob fezza
Mar 24, 2022
★
★
★
★
★
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
