TRX8684

Overview

The Traxxas Output centre Differential, hardened Steel (2 pcs) TRX8684 is a premium drivetrain upgrade designed for RC enthusiasts who demand maximum durability and performance from their vehicles. Whether you're running an E-Revo 2.0 or another compatible Traxxas model, these hardened steel output cups represent a significant step up from standard components, offering the strength needed for aggressive driving and competitive use. This is an essential upgrade for anyone serious about RC car UK performance, from weekend bashers to dedicated racers who want to push their vehicles to the limit without worrying about drivetrain failure.

Built with Traxxas's commitment to quality and engineering excellence, these centre differential output cups are manufactured to exacting standards using hardened steel construction. The upgrade path from standard to hardened steel components is a well-established way to improve reliability in high-performance RC buggies and trucks across the UK. If you've experienced drivetrain wear, broken output cups, or simply want to future-proof your setup against the stresses of hard driving, these components deliver the robustness you need. The inclusion of 2.5x12 mm drive pins ensures complete compatibility with your existing driveshaft setup.

RC Model Shop stocks this genuine Traxxas spare part as part of our comprehensive range of drivetrain upgrades and performance components. For users of brushless RC cars and trucks, a strong centre differential is crucial for transmitting power reliably from the motor through to the wheels, especially when running high-power setups. These hardened steel output cups work seamlessly with both standard centre driveshafts and the upgraded 9655X hardened steel centre CV driveshafts, giving you flexibility in how you configure your drivetrain.

Key Features

• Hardened Steel Construction — These output cups are manufactured from hardened steel rather than standard material, providing dramatically improved durability and resistance to wear, stripping, and failure under high torque loads. This is especially valuable if you run a brushless motor or regularly drive at full throttle in aggressive conditions.
• Heavy-Duty Centre Differential Upgrade — Designed specifically for the centre differential application, these cups handle the critical task of transferring power from your driveshaft to the wheels with minimal loss and maximum reliability, making them an ideal upgrade for serious RC enthusiasts.
• Compatible with Standard and Upgraded Driveshafts — These hardened steel output cups work with both standard centre driveshafts and the premium 9655X hardened steel centre CV driveshafts, allowing you to build your drivetrain exactly as you need it without compatibility concerns.
• Includes Drive Pins — Each pair comes complete with 2.5x12 mm drive pins (2), ensuring you have everything needed for installation without requiring additional purchases or hunting through spare parts bins.
• Sold in Pairs — You receive two output cups per package, which is the correct quantity for a complete centre differential setup on most RC vehicles, eliminating the need to buy multiple packs.
• Genuine Traxxas Component — As an official Traxxas spare part, this component meets all factory specifications and engineering tolerances, ensuring perfect fitment and performance with your Traxxas RC vehicle.

Technical Performance

From a technical standpoint, the centre differential is one of the most critical components in any RC drivetrain. The output cups are where the driveshaft connects to transmit rotational force, and under high-power brushless motor conditions or aggressive driving, these components experience significant stress. The upgrade from standard material to hardened steel dramatically increases the lifespan and reliability of this connection point. The hardening process used by Traxxas increases the material's hardness and resistance to deformation, meaning the engagement surfaces that mate with the drive pins maintain their shape and grip even after hundreds of run hours. This translates directly to less slop in the drivetrain, better power transmission efficiency, and fewer catastrophic failures during important races or runs. The 2.5x12 mm drive pins are precision-engineered to work with these cups, creating a secure mechanical lock that prevents any unwanted rotation or slipping between components. Whether you're running a ready to run RC or a finely tuned competition vehicle, the quality of your centre differential components directly affects how well your vehicle performs and how long it lasts between maintenance intervals. For users pushing their vehicles hard, especially on UK tracks or rough terrain, this upgrade is a preventative investment that will save money on replacement parts over time.

What's in the Box

• Hardened steel centre differential output cups (2 pcs)
• 2.5x12 mm drive pins (2)

Frequently Asked Questions

• What is a centre differential output cup and why does it matter for my RC car? — The centre differential output cup is a critical component in your RC vehicle's drivetrain that connects the driveshaft to the differential mechanism. It's responsible for transferring rotational force from the motor, through the driveshaft, and into the wheels. Standard output cups can wear, strip, or break under high torque, especially with brushless motors or aggressive driving. Upgrading to hardened steel cups significantly improves durability and reliability, reducing drivetrain failures and maintaining consistent performance run after run.
• Will these hardened steel output cups fit my Traxxas model? — These cups are designed for Traxxas vehicles that use centre differential setups, including the E-Revo 2.0 and compatible models. The TRX8684 part number is the correct specification for these applications. If you're unsure about compatibility with your specific vehicle, check your owner's manual or contact our knowledgeable team at RC Model Shop, and we'll confirm fitment before you purchase.
• Do I need to buy anything else to install these output cups? — The package includes the two output cups and the necessary 2.5x12 mm drive pins, so you have all the direct components needed for installation. You may need basic tools like hex wrenches depending on your vehicle's design, but no additional drivetrain parts are required.
• What's the difference between these hardened steel output cups and standard ones? — Standard output cups are typically made from softer materials that can wear, become stripped, or break under high torque loads. These hardened steel versions have been heat-treated to increase their hardness and durability, making them significantly more resistant to wear and failure. The investment in hardened steel is particularly worthwhile if you run brushless motors, drive competitively, or bash hard.
• Are these suitable for beginners or just advanced users? — While these are high-quality upgrade components, they're a spare part rather than a complete vehicle, so they're best suited for users who already have a Traxxas RC vehicle and want to improve its reliability. If you're new to RC and looking for something ready to run, you'd want to start with a complete RTR vehicle first, then consider upgrades like these once you're familiar with the hobby.
• How long will these output cups last? — The hardened steel construction provides excellent longevity compared to standard material. Lifespan depends on driving intensity, terrain, motor power, and maintenance, but these components typically outlast their standard equivalents by a significant margin, making them a cost-effective upgrade over time.

Why Buy from RC Model Shop?

RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the Traxxas Output centre Differential, hardened Steel (2 pcs) TRX8684 today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.