Traxxas Differential, Rear (fully assembled) TRX8576

Overview

The Traxxas Differential, Rear (fully assembled) TRX8576 is a genuine OEM replacement part designed specifically for the Traxxas UDR (Unlimited Desert Racer) series of pro-scale 4WD short course trucks. This fully assembled rear differential comes ready to install, eliminating the need for time-consuming assembly and tuning. Whether you are a serious RC enthusiast looking to maintain peak performance on your Traxxas UDR, or you need a replacement after wear and tear from intense off-road driving, this genuine Traxxas component ensures your RC short course truck operates at its best. The UDR is renowned for its incredible scale realism, powerful brushless motor system, and exceptional handling characteristics, and the rear differential is a critical component that directly affects traction, cornering stability, and overall drivetrain performance across all terrain types.

For RC car UK enthusiasts who demand quality and reliability, choosing genuine Traxxas parts is essential. The TRX8576 rear differential maintains the factory specifications and engineering that made your UDR a performance leader in the ready-to-run RC truck category. This fully assembled differential arrives pre-filled with SAE 500k silicone oil, the factory-standard differential fluid that provides optimal viscosity for smooth power delivery and controlled slip during acceleration and cornering. Installing this component is straightforward for users familiar with RC maintenance, making it an ideal upgrade or replacement for dedicated RC bashers and competitors alike.

The rear differential is a transmission tune-up component that significantly impacts how your brushless RC short course truck handles power transfer to the rear wheels. A quality differential allows the inner and outer wheels to rotate at different speeds during turns, which is crucial for maintaining traction and reducing tyre scrub on concrete, dirt, carpet, and mixed terrain. This genuine Traxxas part is engineered to withstand the demands of high-performance RC driving, whether you are running casual weekend bashing sessions or pushing your UDR to competitive limits on the track.

Key Features

• Fully Assembled and Ready to Install — This rear differential arrives completely assembled from the factory, eliminating the need for time-consuming component assembly and setup. Simply remove your old differential and bolt this unit into place, saving valuable time and reducing the risk of incorrect assembly that could compromise performance.
• Factory Pre-Filled with SAE 500k Silicone Oil — The differential comes pre-filled with genuine Traxxas SAE 500k silicone oil (part number TRX5039), ensuring you get the exact factory-standard viscosity and fluid specifications that Traxxas engineers calibrated for optimal performance in the UDR platform. This removes the guesswork from differential setup and tuning.
• Genuine OEM Traxxas Component — This is an authentic Traxxas factory part designed and manufactured to the exact same specifications as the differential installed in new UDR trucks. Using genuine parts ensures compatibility, durability, and performance that matches the original equipment.
• Compatible with Multiple UDR Variants — This rear differential is compatible with both the Traxxas UDR Unlimited Desert Racer Pro-Scale 4WD RTR Short Course Truck with Fox Racing suspension and the Rigid Industries variant, making it a versatile replacement or upgrade component for UDR owners with either suspension package.
• Precision Engineered for Desert Racing Performance — The UDR rear differential is designed to handle the extreme demands of high-speed desert racing, with precision gears and internal components that distribute power smoothly to both rear wheels whilst allowing speed differentiation during cornering, which is essential for maintaining traction on rough, uneven terrain.
• Improves Traction and Cornering Stability — A quality differential allows the outside wheel to spin faster than the inside wheel during turns, which reduces tyre scrub, improves steering response, and maintains better overall traction during acceleration and deceleration across varied RC driving surfaces.

Technical Performance

The Traxxas TRX8576 rear differential represents precision engineering designed for the demanding requirements of the UDR pro-scale 4WD short course truck platform. As a transmission tune-up component, this differential is critical to the drivetrain's ability to transfer the brushless motor's power to the ground efficiently whilst maintaining control during dynamic driving situations. The fully assembled construction means all internal gears, bearings, and precision components are factory-calibrated and tested before shipment, ensuring you receive a unit that performs to exact Traxxas specifications. The SAE 500k silicone oil fill provides the ideal balance of viscosity for the UDR's gearing and operating conditions—fluid too thick reduces responsiveness and increases drag, whilst fluid too thin fails to provide adequate protection and control during high-load cornering. For owners of the brushless-powered UDR with its powerful electric motor system, this rear differential ensures that aggressive acceleration and high-speed driving translate into controlled, predictable power delivery to both rear wheels. The differential's internal design allows the outer wheel to rotate faster than the inner wheel during turns, which is absolutely critical for maintaining traction on desert terrain, hardpack dirt, carpet track surfaces, and mixed-surface courses. This component withstands the stresses of 4WD performance driving and is engineered with the same durability standards as all genuine Traxxas parts, making it suitable for both casual RC enthusiasts and serious competitors pushing their UDR to its limits.

What's in the Box

• Traxxas Differential, Rear (fully assembled) TRX8576
• Pre-filled with SAE 500k silicone oil

Frequently Asked Questions

• Is this rear differential compatible with my Traxxas UDR? — Yes, the TRX8576 is specifically designed for the Traxxas UDR Unlimited Desert Racer Pro-Scale 4WD RTR Short Course Truck and is compatible with both the Fox Racing suspension variant (model TRX85086-4-FOX1) and the Rigid Industries suspension variant (model TRX85086-4-RGD1). Always verify your UDR model number before ordering to ensure compatibility.
• Does this come with differential fluid already? — Yes, the TRX8576 arrives fully assembled and pre-filled with SAE 500k silicone oil from the factory. This is the genuine Traxxas factory-standard differential fluid (part number TRX5039) that provides optimal performance in the UDR. You do not need to purchase additional fluid unless you plan to adjust the viscosity for tuning purposes later.
• Do I need any special tools to install this differential? — Installation difficulty depends on your mechanical experience and familiarity with RC truck maintenance. You will need basic RC tools including hex drivers and potentially a differential tool if you need to remove the old differential. If you are unfamiliar with RC maintenance, RC Model Shop staff can provide guidance on the installation process.
• What is a differential and why does it matter for my RC truck? — A differential is a crucial drivetrain component that distributes power from the motor to both rear wheels whilst allowing them to spin at different speeds during turns. Without a differential, both rear wheels would be forced to spin at the same speed, causing excessive tyre scrub during cornering and reducing traction. A quality differential improves handling, steering response, and overall performance, making it one of the most important tune-up components for any 4WD RC short course truck or desert racer.
• Can I adjust the differential fluid viscosity for performance tuning? — Yes, the differential fluid viscosity affects how the differential behaves during driving. SAE 500k is the factory standard and provides balanced performance across most conditions. Some users experiment with thicker or thinner oils depending on track conditions and driving style—thicker fluid provides more locking effect and better traction in loose terrain, whilst thinner fluid reduces drag and improves responsiveness. However, the factory SAE 500k specification is recommended for general use.
• What is the difference between this fully assembled differential and component alternatives? — The TRX8576 arrives fully assembled and pre-filled with fluid, meaning you can install it directly without any assembly or tuning. This saves time and eliminates assembly errors. Alternative options might require you to purchase individual components and assemble them yourself, which demands additional knowledge and time investment. For most users, the convenience and reliability of a factory-assembled differential outweighs the minimal cost difference.

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 Differential, Rear (fully assembled) TRX8576 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.