03-07 Factory bolt size is 9/16" (14mm)
07.5 Trucks were a mixed bag and had varying bolt sizes. Some had 5/8" (16mm), some had 9/16" (14mm), and some had a mix of the two. Please check your bolts to determine which you need.
08-13 2500 and 08-12 3500 Factory bolt size is 5/8" (16mm)
14+2500 and 13+ 3500 Factory bolt size is 18mm
| Bolt Diameter | Select or 18mm or 5/8 or 9/16 |
See It Installed
Install videos and build guides on our YouTube channel.
Watch more installs on YouTubeReviews from Google
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132 reviews
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Ajay Paynter
Mar 4, 2026
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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.
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Ryan Colligan
Mar 4, 2026
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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.
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Marcus Torres
Jan 15, 2026
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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.
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Sebastian
Oct 24, 2025
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Great products they sell, got a crawl series long arm kit for my xj and it has held up quite nice, they are beefy, and for what ever reason they fail it has a great warranty with a customer service to match, when someone asks what control arm kit to buy I always recommend core 4x4
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Ryan Rogers
Aug 25, 2025
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I purchased a set of the Cruiser Series control arms for my Jeep Jk based on postive reviews from different Jeep Facebook pages. Ordered and 2 days later realized they had the very same exact arms on sale in the overstock section. Called them up and they refunded me the savings from my original purchase. Amazing, honest service. Can't wait to get them installed. Keep up the good work guys.
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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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Ma TheMeatLoaf
Mar 23, 2024
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Their website estimated 2 days to get my parts but actually took 11. No communication to let me know what’s going on. Parts were missing. Some days they answer questions, some they don’t. Didn’t let me know I’d have to alter stock bolts to fit their parts.
All around just seems like they don’t care.
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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
NM
Noah Myers
Mar 23, 2024
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I contacted these guys on a Saturday through email and needed some control arms by the following weekend, Spence got back with me and told me he would make sure the order got shipped out on Monday, they got busy and wasn’t able to ship the package out so he got back with me that evening and upgraded my shipping for free and shipped out the next day, only because he told me he’d make sure I’d have them by the weekend! This company sticks to their word! The customer service from these guys are unmatched and they will have another lifetime customer here!
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Owen Adams
Sep 24, 2025
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These guys are awesome I messed up my address on my order somehow and they were so so helpful Korby was right there every step to a solution very communicative and respectful I will definitely be ordering parts with them in the future!