Tesla Model S / Model S Plaid (2021 – 2026+) Billet Rear Trailing Arm Set (Lower Aft Link)

The rear trailing arm, or lower aft link, locates the rear wheel and helps control how it moves under load in the 2021+ Model S five-link rear suspension. This billet set replaces the standard lower link with a stronger, lighter billet aluminum version running sealed spherical bushings. That upgrade removes the compliance of rubber, so the rear wheel is held more precisely, which improves handling feel and durability without adding noise.

Rubber bushings flex under cornering and braking, which lets the wheel move slightly and blurs your inputs. The sealed spherical bushings on this arm remove that slop for more precise, consistent wheel location, and being sealed they also operate silently and resist wear. You get the sharper feel and durability of a spherical joint without the harshness or noise that open uniballs can introduce on a street car.

Yes. It is designed for the Tesla Model S and Model S Plaid from 2021 through 2026 and up, covering the all-new five-link rear suspension Tesla introduced on the current car. The set replaces Tesla part number 1420452-99-C, the rear lower aft link, and the SKU is UP-MSMX2-113-1.1. An early 2021 Model S and a current-generation car both take this same arm.

It is CNC-milled from 6061 aluminum for maximum strength while saving weight, and it is optimized with FEA simulation to ensure strong static, dynamic, and fatigue performance. The design was stress-modeled before production, so the strength is engineered rather than assumed from how it looks. Unplugged Performance developed its Model S suspension program on the Dark Helmet race car, so parts like this come from real racing and street testing before public release.

It ships next business day and is a bolt-in replacement for the factory lower aft link, so a capable owner with a lift and proper tools can fit it, ideally followed by an alignment. If you would rather not, Unplugged Performance can install it at our Hawthorne shop and our team will provide a quote and appointment. Because it is a suspension link, correct torque and a follow-up alignment matter for the best result.

You can buy it individually or as part of a comprehensive lineup, depending on your goals. We recommend pairing it with the rest of the rear suspension family, including the Billet Rear Traction Arm Set and the Billet Adjustable Rear Camber Arm Set. Doing the whole rear at once gives the most cohesive handling gain, but this single arm is still a worthwhile strength and precision upgrade on its own.

No. The sealed spherical bushings are chosen specifically to add precision and durability with silent operation, so you sharpen wheel control without the drone or harshness that plain uniballs can bring. The billet aluminum construction is stronger and lighter than the factory link, and the result is improved handling feel rather than a punishing ride. It is a street-friendly precision upgrade, not a compromise you feel every day.

Development kicked off in June 2021 with the Dark Helmet race car, aimed at building the ultimate handling Model S. That program brought home a Pikes Peak class victory and multiple production-based EV lap records. Every suspension part begins with precise 3D scanning of the car’s suspension to create a digital model, then real-world racing and street testing on company cars before it reaches customers. This arm is a direct product of that process.

By replacing a flexy rubber-bushed link with a stiff billet arm on sealed spherical bushings, the rear wheel stays where the geometry intends under cornering and braking loads. That tightens turn-in response and improves stability, giving more consistent, predictable rear behavior as you push harder. It also adds durability. The gain is about precision and control rather than outright grip, which you build with tires and alignment.

Installing them does not automatically void your Tesla warranty. Under the Magnuson-Moss Warranty Act, Tesla would have to prove the aftermarket arm caused a specific failure to deny a claim, so keep your factory link if you want the option to revert. Unplugged Performance also backs its suspension parts with an industry-leading warranty, which is part of why the company positions these as the best money can buy.

Tesla’s warranty covers factory-installed parts, but it does not automatically void your warranty if you install aftermarket components like Unplugged Performance brake kits. Under U.S. law (Magnuson-Moss Warranty Act), Tesla must prove that an aftermarket part caused a failure in order to deny warranty coverage. Our parts are engineered to work harmoniously with Tesla OEM Brake systems and can be professionally installed by Unplugged Performance in Hawthorne, CA or by an authorized installer to minimize risk. That said, any damage directly caused by misuse or improper installation may not be covered. We recommend retaining all factory parts so you can revert to stock if needed. Many Tesla owners enjoy peace of mind by using Unplugged Performance products, which are extensively tested and installed by certified professionals. If warranty concerns are top-of-mind, our team can help clarify compatibility and installation best practices to ensure a worry-free experience.

Unplugged Performance offers a comprehensive warranty on all parts and installations performed by our certified technicians. Warranty coverage applies to defects in materials and workmanship on items including lowering springs, coilovers, big brake kits, brake pads, stainless steel brake lines, shocks, and more. Should any covered part fail under normal use or display premature wear, we will repair or replace it at no additional cost—assuming the component was installed by us or at one of our authorized partners.

This warranty is valid for 2 years or 24,000 miles, whichever comes first, excluding consumable products like brake pads, rotors, and tires, starting from the installation date. Coverage extends to labor for warranty repairs when performed by Unplugged Performance or an authorized installer. It does not cover damage resulting from misuse, accidents, off‑road use, improper installation not done by us, or modifications that aren’t factory-approved.

To file a warranty claim, simply contact our service team. We’ll guide you through inspection, shipping (if needed), and repair or replacement logistics. transparencia and top-tier support are what you can expect from Unplugged.

Installing aftermarket parts does not automatically void your Tesla warranty. Under the Magnusson-Moss Warranty Act (www.sema.org/sema-enews/2011/01/ftc-validates-right-to-install-aftermarket-parts), a manufacturer cannot void your warranty simply because you installed aftermarket parts. Tesla must prove that the aftermarket part caused the specific failure in question to deny a warranty claim. UP recommends retaining all factory parts to allow reverting to stock if needed. 

To find authorized installers or retailers of Unplugged Performance products in your area, please use the form on our website to provide your location details. This will help us connect you with an authorized installer nearby. You can find the form here.

Unplugged Performance processes orders quickly, typically within 1–2 business days after placement. For U.S. customers, orders under $50 usually ship via FedEx SmartPost with an estimated delivery time of 2–7 business days. Larger items like body kits or bumpers may ship via freight carriers with curbside delivery; customers will be contacted to schedule a delivery window. International shipping is available to most countries, with shipping costs calculated at checkout. Delivery times abroad vary, generally ranging from 5 to 16 business days depending on destination. Import duties or taxes are the customer’s responsibility. To ensure a smooth shipping experience, provide accurate contact information during checkout. For specific questions or shipping quotes, Unplugged Performance’s support team is available to assist.