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
Details
Core 4x4's Crawl Series rear upper control arms replace the worn factory stamped-steel arms on the GMC Yukon XL Denali (2001–2006). The factory arms use soft rubber bushings and a fixed length, so there's no way to correct pinion angle after a lift or leveling kit. These Core 4x4 arms are a serious step up: DOM steel tubing and forged Rock Jock Johnny Joints at both ends for maximum articulation, with adjustable length to set rear pinion angle back to spec.
Includes: Rear upper control arms (pair); mounting hardware (bolts, nuts, and washers).
Specs:
- Tubing — 1.5 in. o.d. × 5/16 in. wall DOM steel
- Joints — forged Rock Jock Johnny Joints, both ends (double-threaded)
- Adjustable length — for pinion-angle correction
- Lift range — 0–6 in. and up
- Made in the USA
- Lifetime warranty — bend it or break it, we'll replace it
- Wear items (bushings, joints) — covered for 18 months
Suspension Type — Factory Autoride (Z55): Chances are, your truck came with rear Autoride (Z55) from the factory — GM's air-leveling system. This part is built to match: the ride-height sensor mounting tab is included on both rear upper arms, so your factory sensors bolt right back on. Converted to coil springs — or never had air ride at all? No problem — everything fits and works exactly the same; the sensor tabs just go unused.
Notes:
- Hardware is included with your arms. If you ever need replacements down the road, the matching kit is available separately.
- Running a lift? The 4-piece rear set (CRL-G-800-DXL-RS4-Z55) adds the matching lower arms to replace all four rear arms in one job.
Parts:
- Forged Rock Jock Johnny Joint, right-hand — CE-9112N-22 (1 per arm, 2 for the pair).
- Forged Rock Jock Johnny Joint, left-hand — CE-9112NL-22 (1 per arm, 2 for the pair).
- Replacement hardware kit — CRL-G-800-RU2-HWK.
Fits:
- Chevy Tahoe (2000–2006)
- Chevy Suburban 1500 (2000–2006)
- Chevy Avalanche 1500 (2002–2006)
- GMC Yukon / Yukon XL 1500 (2000–2006)
- GMC Yukon Denali / XL Denali (2001–2006)
- Cadillac Escalade / ESV / EXT (2002–2006)
- 1500-series only. Does NOT fit 2500-series HD.
Built With
Tubing: 1.5" OD, 5/16" wall DOM · Joints: Rock Jock Johnny Joints, both ends
| Make | Model | Submodel | Years |
|---|---|---|---|
| GMC | Yukon XL Denali | 2001 - 2006 |
Construction & Materials
Tubing: 1.5" OD, 5/16" wall DOM · Joints: Rock Jock Johnny Joints, both ends
| Brand | CORE 4X4 |
| Color | Black or Blue or Charcoal or Green or Light Green or Orange or Purple or Red or White or Yellow |
| Lift Size | 0" — 6" or 6"+ |
| Series | Crawl Series |
Use the vehicle selector on our website to shop by your year, make, and model. On product pages, use the kit builder to select your color, series, lift height, and any add-on options, then add to cart. If you need help, call or email our team.
Standard orders typically ship within 1–3 business days of ordering. Custom color orders take approximately 5–10 business days. Because everything is built in-house, we can turn orders quickly even for custom specifications.
You can reach our team through the contact form on our website, or browse to the Contact Us page. Our team is available to answer pre-sale and technical questions before and after your purchase.
Reviews of Core 4x4
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132 reviews
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Zen Asher
Mar 23, 2025
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The quality and durability of the arms are the best. They are super heavy duty. And lifetime warranty is crazy
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niceguyr1
Mar 24, 2023
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I purchased upper and lower adjustable arms for my WJ and lowers were missing the spacers. I didn't know until 3 months later when I was installing them. With absolutely zero hassles they quickly sent me the missing spacers. Fantastic product and service! Huge thank you guys for the awesome service and parts!!! Customer service is quickly becoming a lost commodity and you guys gave me hope that it's still alive and well, you just have to buy from the right people... Thanks again for going above and beyond! 👍👍
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Aaron Lake
Apr 27, 2025
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Korby was a great help with getting me a set of leaf springs for my Cherokee. Great customer service and an awesome product all made in the USA. Proud to support and rock their parts on my vehicle. 👍 …
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Brantly Musgrave
Jan 22, 2026
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First and foremost would like to say that Core4x4s customer service is top notch and they definitely stand behind their warranty on products! Highly recommend using them for any of your off road needs! It’s rare to find a company now a days that backs their products and they do!
Had a few issues with mounts and control arms and they handled it without hesitation! Thank you!
MP
Mirko Pompili
Mar 19, 2026
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I want to share a truly positive experience.
I ordered a car kit consisting of two packages, but unfortunately one was lost during shipping with UPS. The situation could have become complicated... but it didn't.
The company manager was extremely helpful and professional: he personally followed up on the situation and did everything he could to resolve the issue, even sending me the package again without hesitation.
It's rare to find such attentive and reliable customer service these days.
My sincere congratulations on your professionalism and commitment: that makes all the difference.
RH
Rex Hodges
Jun 26, 2025
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After ordering an upper and lower adjustable control arm kit manufactured by CORE 4X4 from a jeep parts distributor who's intials are E.T., they came with 3 of the threaded ends missing. After over 2 months of phone calls and emails to this E.T. company nothing was resolved. I finally decided to call CORE 4X4 myself and tell them my dilemma. I spoke with a very personable and professional gentleman named Korby, who is one of CORE 4X4's representatives, after a brief discussion of what I went thru he simply asked me for a picture and some measurements and the items I was missing and asked if I could cover ONLY the cost of shipping and I had my missing parts in exactly 1 weeks time. This company not only builds all it's parts in the U.S.A., they stand behind their products with great customer service and life time warranty. My experience with this company and their Rep Korby was fantastic. I would definitely recommend CORE 4X4 to anyone who needs parts for any 4x4 projects. You just can't beat their quality and service.
Rex Hodges
Valparaiso, Indiana
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David Rogers
Aug 25, 2025
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Ive had the front adjustable control arm kit in bright green for my 1996 ZJ.
Ive had the kit for about a year now and i have to say, im extremely impressed, over 1000 miles off-road and roughly 20,000 miles on the highway. These control arm kits for any vehicle built by core 4x4 are well worth the money, just be aware thereight be some minor scatches or chips from shipping ( but who should care about that if you're beating the crap out of em' they way they were built and designed for)
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Brayden Brockey
Mar 23, 2024
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Got a set of upper control arms for my xj, really impressed with the quality
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John Cutler
Oct 24, 2025
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In September 2025, we visited CORE 4x4 in Orem, Utah. CORE 4x4 makes control arms and other similar parts that stiffen the suspension of an off-road 4x4 vehicles, so that the off-road vehicles can travel on more rugged terrain. CORE 4x4 used to share this building with another business, and since this other business has moved elsewhere, CORE 4x4 will continue to expand and grow their business. Good for CORE 4x4 to be a growing company and to expand into the vacant part of the building.
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Aaron
Mar 23, 2024
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I have recently come to know Core 4x4 when I purchased a Jeep XJ and was looking for a place that had dedicated XJ suspension and components. Here is what makes them different than most other shops. All of their components are top shelf quality and they back it up if you break any of it. I was able to see their shop when I picked up an order locally and was impressed with their attention to detail and how they assemble and powder coat each part. I had an issue with a shackle and needed the threaded shaft to be shorter. I called in and talked to Kaden and he told me to come by and they would shorten it for me. When I got there, Kaden and Spencer (the owner) met me and talked about options and proceeded to make the right adjustments to fit my XJ. Told me if anything changes in the future and I need additional length, they would take care of me. So what really sets them apart from others is their Customer Service. Try calling in to any other Jeep suspension or part shop and see how they treat you. Been there - done that.
Will continue to do business with Core and their team. Getting that kind of service for just a shackle has me thinking I may need to replace my JT components with Core's. Thanks Guys for being helpful good humans!
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Specifications
| Color | Black, Blue, Charcoal, Green, Light Green, Orange, Purple, Red, White, Yellow |
| Lift Size | 0" — 6", 6"+ |
| Brand | CORE 4X4 |
| Series | Crawl Series |
| Tags | |
|---|---|
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