Standard endlink bolt size is 12mm for most applications. Some ram 1500 trucks that utilize a welded nut on the frame end of the rear endlinks will use 10mm hardware.
Track bar bolt sizes vary based on jeep model and track bar location. Measure current setup, or reach out to us to determine factory size based on your vehicle.
| Bolt Diameter | Select or 10mm or 12mm 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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Peter Busack
May 27, 2025
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Purchased a set of Trailing arms for my Ram 1500, quality is first class. I bought the ones with the Jonny Joints for more articulation and it appears from the construction I should get a lifetime of use, Zerk fittings are an added plus. Would defiantly recommend, and the the service team answered all of my questions.
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jacob fezza
Mar 24, 2022
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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
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Danny
Oct 24, 2025
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Outstanding customer service to match the high quality parts. This is the go-to company.
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Singer Heating and Cooling
Mar 25, 2018
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These guys are great. You can get them on the phone for support. This important and is not always the case with other custom parts builders. Their control arms are bomb proof and offer plenty of options. You can get real genuine Currie Johnny joints without paying the price for Currie arms.
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DANIEL DUSSAULT
Nov 23, 2025
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Very beefy items for a very reasonable price. Personally have CORE rear track bar and all upper control arms for my 04 Jeep TJ. Had a slight issue with control arm length and they went above and beyond to swap jam nuts to get me where I needed to be. Really have to appreciate a company like this.
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Chris
Oct 24, 2025
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Great product for a good price. Customer service is top notch, I had an issue which was self cause and Core 4x4 helped me out even though it was my own fault. Would definitely recommend and use them again.
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Fernando Salazar
Aug 25, 2025
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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!