Overview
The Traxxas Portal Drive Gear Set (Rear, Left or Right) TRX9878 is an essential replacement and upgrade component for Traxxas TRX-4M scale crawler enthusiasts across the UK. Whether you're maintaining your RC crawler after intensive off-road bashings or looking to upgrade your drivetrain for enhanced performance, this genuine Traxxas portal drive gear set delivers the quality and reliability you expect from the world's leading RC vehicle manufacturer. Portal drive systems are a cornerstone of modern RC rock crawling and off-road driving, allowing for improved ground clearance and better weight distribution that gives your RC car the advantage it needs to conquer challenging terrain.
This rear portal drive gear set is specifically engineered to fit either the left or right side of your TRX-4M, making it a versatile replacement option for any damage or wear to your existing portal drive gears. As a dedicated RC car UK enthusiast, you'll appreciate that Traxxas spare parts are manufactured to the same exacting standards as their complete vehicles, ensuring that your replacement components integrate seamlessly with your existing drivetrain and maintain the factory performance characteristics your TRX-4M was designed to deliver. The portal drive system is fundamental to the TRX-4M's legendary crawling ability, and keeping your gears in optimal condition is essential for maintaining the precision handling and torque delivery that makes this vehicle the choice of serious RC crawler drivers.
Perfect for bashers, weekend warriors, and competitive crawlers alike, the Traxxas Portal Drive Gear Set TRX9878 is a straightforward maintenance item that takes the guesswork out of drivetrain repairs. Rather than replacing entire assemblies, this targeted gear set allows you to address specific wear points in your portal drive system, saving you money while keeping your RC crawler performing at its best.
Key Features
- Left or Right Fitment Versatility — This portal drive gear set is designed to fit either the left or right side of your TRX-4M, giving you the flexibility to replace whichever side requires maintenance without needing to stock multiple part numbers. This dual-fitment design simplifies spare parts management for RC hobbyists.
- Genuine Traxxas Engineering — As an official Traxxas spare part, this gear set meets all factory specifications and tolerances, ensuring perfect compatibility with your TRX-4M and maintaining the vehicle's signature crawling performance. Genuine parts provide peace of mind that your RC crawler will perform exactly as Traxxas engineered it.
- Portal Drive System Reliability — The portal drive gears are critical components in the TRX-4M's advanced drivetrain architecture, and replacing worn gears with genuine Traxxas components restores the precision engagement and power delivery your vehicle needs for serious off-road work.
- Easy Installation — As a focused spare part designed specifically for the TRX-4M platform, this gear set integrates directly into your existing drivetrain with no modifications or additional components required, making it ideal for maintenance between bashings or after heavy competition use.
- Part of the Complete TRX-4M Ecosystem — This component works in harmony with other TRX-4M portal drive components such as stub axles and axle shafts, allowing you to build a complete and coordinated drivetrain replacement when needed.
Technical Performance
The Traxxas Portal Drive Gear Set represents the pinnacle of RC drivetrain engineering, specifically tailored for the demanding requirements of the TRX-4M crawler platform. Portal drive systems are engineered to provide superior ground clearance whilst maintaining a low centre of gravity, a balance that is critical for serious RC rock crawling and technical terrain navigation. The gears within this set are precision-manufactured from hardened materials to withstand the extreme torque loads that portal drive systems experience during low-speed, high-traction crawling scenarios. The TRX-4M's portal drive architecture allows the vehicle to achieve exceptional wheel articulation and traction, and maintaining these gears in pristine condition is essential for preserving the vehicle's ability to traverse boulder fields, rocky slopes, and other challenging off-road environments. Each gear tooth is meticulously engineered to mesh perfectly with complementary components, ensuring smooth power delivery and minimal backlash. The rear portal drive gears specifically manage the power transfer from the transmission to the rear wheels, making them essential for maintaining the vehicle's climbing ability and off-road control. Whether you're replacing gears after a particularly challenging crawling session or performing scheduled maintenance on a heavily-used RC crawler, genuine Traxxas replacement gears guarantee that your TRX-4M will continue to deliver the performance and reliability it's renowned for throughout the UK RC community.
What's in the Box
- Traxxas Portal Drive Gear Set for rear axle (left or right fitment)
Frequently Asked Questions
- Will the Traxxas Portal Drive Gear Set TRX9878 fit both sides of my TRX-4M? — Yes, this is one of the key advantages of this part number. The portal drive gear set is designed to fit either the left or right side of your TRX-4M's rear axle, making it a versatile solution when you need to replace either portal drive on your vehicle. This dual-fitment approach means you only need to stock one part number for either side.
- How often do portal drive gears need replacing? — Portal drive gears are durable components, but they will wear over time depending on usage intensity. Heavy bashers and competition crawlers who regularly push their vehicles to the limit may need to replace gears more frequently than casual hobby drivers. Regular inspection during maintenance is recommended, and replacement should be considered if you notice any grinding noises, slipping, or loss of climbing power.
- Is this a genuine Traxxas part? — Yes, the TRX9878 is an official Traxxas spare part manufactured to factory specifications. When you purchase from RC Model Shop, you're receiving genuine Traxxas components, not aftermarket replacements. This guarantees compatibility and performance with your TRX-4M.
- What tools do I need to install this gear set? — Whilst the specific tools required depend on your mechanical skill level and experience with RC vehicle maintenance, installation of this rear portal drive gear set typically requires standard RC hobby tools. We recommend consulting your TRX-4M user manual or contacting our expert team at RC Model Shop for detailed installation guidance specific to your vehicle.
- Can I use this part on other Traxxas models? — This gear set is specifically engineered for the TRX-4M platform. Whilst Traxxas makes many excellent RC vehicles, portal drive systems vary between models, so compatibility is limited to the TRX-4M. For other models, you should verify the correct part number before purchase.
- What is the difference between left and right portal drive gears? — Portal drive gears are mirrored components — the left gear set is the mirror image of the right gear set, allowing them to mesh correctly with the portal drive hub assembly on each side of the vehicle. This left/right design is why a single part number can serve both sides of your TRX-4M.
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 Portal drive gear set, rear (left or right) TRX9878 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.
- Brand: Traxxas
- Model Number: TRX9878
- Product Type: Rear Portal Drive Gear Set
- Vehicle Compatibility: TRX-4M
- Fitment: Left or Right side
- EAN Code: 020334011626
- Spare Part Category: Drivetrain Spares
- RRP: £9.75
We want to make sure your delivery goes smoothly, so here are some important details about our service:
- For orders above £120, we offer delivery to most mainland UK addresses. For orders under £120, we can still deliver to Northern Ireland and the outlying isles, as long as the item can be sent by Royal Mail, weighs less than 30kg, and fits within 61cm × 46cm × 46cm. Some highland and remote areas may carry an extra delivery charge as couriers often apply surcharges in these locations. If you live in one of these areas, feel free to contact us before ordering so we can confirm the delivery options and costs for you.
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