Skip to Content
ADD YOUR JEEP — FIND EXACT-FIT PARTS
Shop
LIFETIME WARRANTY Non-wear items BUILT TO ORDER Ships within 3 days MADE IN USA · Orem, Utah

24.00 24.0 USD 24.00

24.00

More payment options ▾

BUILD MY KIT →

🔧 Built to order · Ships in 1–3 business days

https://jerdev.core4x4.com/web/image/product.template/24491/image_1920?unique=b5566ad

RockJock JL/JT Front Coil Spring Shim, Axle Side, 1/4 in. thick

SKU: RJ-107100-3
Fits: 2020 - Present Jeep Gladiator JT Add vehicle

24.00 24.0 USD 24.00

24.00

  • Vehicle
    Confirm this matches your vehicle. Use Shop by Vehicle to filter correctly.
  • 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
Ships in 3 Days From our UT facility
Fully Adjustable 0-6" of lift
3 X-Series Options Only Core 4x4

RockJock's front coil spring shim for JL Wrangler and JT Gladiator is 1/4 in. thick and mounts between the welded on coil spring axle pad and the coil spring isolator. The indexing pin in the coil spring isolator fits thru the hole in this shim to properly clock it. These shims are used to fine tune vehicle height per model, engine combination and added weight load. Shims may be stacked a maximum of 2 high. Semi-gloss black powder coat finish.

Make Model Submodel Years
Jeep Gladiator 2020 - Present
Jeep Wrangler 2018 - Present

Vehicle Jeep Gladiator JT (20–Present) or Jeep Wrangler JL / JLU (18–Present)
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 YouTube
Google

Reviews from Google

See all on Google
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!!!
WT
William Turton Nov 23, 2025
Google
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
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.
SA
Samuel “SamDaman904” Anscher Mar 23, 2024
Google
I meant to put this reviewing about a year ago now, but ever since I’ve had the core 4 x 4, upper and lower control arms on my 2017 ram 1500, they have worked flawlessly leave been on many offering chips, and I’ll definitely be buying new accessories from them in the future and their new upper control arms that they’re offering for all of the ram trucks. Fantastic customer service fantastic health very automotive, off-road, friendly, and any aftermarket thing for your truck or SUV that they currently have!
RH
R and H H Oct 24, 2025
Google
Top notch company. Mechanic lost bolts that clamp upper control arms. Korby sent out spare bolts no charge. Best customer service I’ve come across in a long time. Only suspension brand I’ll ever use.
JO
Jaime Overmyer Nov 23, 2025
Google
Korby was extremely helpful in helping me find the right part for my truck. He was kind, knowledgeable, and patient while I asked a million questions. He also went out of his way to find the right shipping option for me since it’s tricky where I live. I’m looking forward to getting the parts so I can fix my truck and go adventuring again soon!
HK
Harold Kruder Mar 23, 2024
Google
I needed some parts and had to replace 1 lower control arm and their customer service is great. Helped with answering my questions and got parts shipped quickly.
DD
Dmitriy D May 27, 2025
Google
Installed rear and upper control arms and track bar on my 3rd Gen 4RUNNER to align rear axle and restore factory wheel base after 3.5" lift. Car drives better than New! Improved handling cornering and overall driving. Very solid and high quality made product. Support is outstanding. Shipping extremely fast. Thank you so much. I wish you will have something new for my car.
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
DW
Darin Wuebbels May 27, 2025
Google
Thanks for the fabulous customer service. Your products and customer service are first class. I highly recommend these guys. Excellent experience.
Add your vehicle
Loading…
Add vehicle
SHOP BY VEHICLE
Home