This high-quality Diff Case 37T Main Gear set provides replacement parts for your kit supplied items.
- Manufacturer: ARRMA
- Manufacturer Part Number: AR310872
- Retailer Part Number: Z-AR310872
- EAN: 5052127030502
- Product Type: Differential Case and Ring Gear Assembly
- Category: Drivetrain Spares / Transmission Components
- Main Gear Tooth Count: 37T
- Material: Tough Composite
- Construction Type: Integrated Ring Gear and Diff Case
- Includes: 1 x Ring Gear with Integrated Diff Case, 1 x Diff Case Cap
- Requires: Differential Pinion Shaft Assembly #ARA311031
- Gear Tooth Configuration: Precision Manufactured
- Designed For: ARRMA BLX 3S Brushless Models
- Compatible Scale Classes: 1/10 Scale and 1/8 Scale
- Compatible Vehicle Types: Monster Trucks, Short Course Trucks, Stadium Trucks, Buggies, Speed Trucks, Stunt Trucks, Street Bash Trucks, Desert Trucks
- Compatible Drivetrain: 4WD, 2WD, and Brushed Variants
- Compatibility: BIG ROCK 223S, BIG ROCK 3S, GRANITE 223S, GRANITE 3S, GRANITE Brushed, GRANITE BOOST 2WD, GRANITE MEGA 665, KRATON 4S, OUTCAST 4S, SENTON 223S, SENTON 3S, SENTON Brushed, SENTON BOOST 2WD, VORTEKS 223S, VORTEKS 3S, VORTEKS BOOST 2WD, INFRACTION 223S, INFRACTION 3S, INFRACTION Brushed, MOJAVE 4S, TYPHON 223S, TYPHON 3S, TYPHON Brushed, TYPHON MEGA 665, VENDETTA 3S
- Precision Engineering: Yes - precision manufactured gear tooth configuration for smooth, trouble-free operation
- Seal Design: High-quality diff case moulding ensures reliable diff seal
- Performance Rating: Designed for extreme operating conditions
Overview
The ARRMA Differential Case Set 37T Main Gear is a high-quality replacement component designed for serious RC enthusiasts who demand reliability and performance from their brushless RC models. Whether you're running a 1/10 scale BLX 3S monster truck, short course truck, stadium truck, or 1/8 scale buggy, this differential case set provides the precision engineering needed to keep your RC car UK-ready for competition or weekend bashing. Built to OEM specifications, this replacement part restores your drivetrain to factory performance standards when wear or damage occurs.
ARRMA is renowned for manufacturing RC vehicles and parts that combine durability with exceptional value, and this differential case set is no exception. The 37T main gear integrated ring gear design represents decades of RC engineering expertise, ensuring smooth operation under the extreme stresses of high-performance brushless driving. Whether you've damaged your differential through aggressive racing or simply need a replacement after extensive use, this authentic ARRMA part delivers the exact specifications your model requires.
This is an essential spare part for anyone serious about maintaining their ARRMA RC vehicle in peak condition. Available at RC Model Shop, we stock genuine ARRMA parts for all the major model ranges, from the iconic BIG ROCK and GRANITE monster trucks to the high-performance TYPHON buggies and SENTON short course trucks. Ordering the correct replacement differential ensures your RC car continues to perform as the manufacturer intended.
Key Features
- Tough Composite Material Construction — The differential case is manufactured from high-quality composite material that provides excellent durability and consistent performance even under extreme operating conditions, which is essential for serious RC car UK racing and bashing applications where impacts and stress are inevitable.
- Precision Manufactured Gear Tooth Configuration — Each tooth on the 37T main gear has been precisely engineered and manufactured to deliver smooth, trouble-free gear operation with minimal backlash, ensuring efficient power transfer from the motor to the wheels without grinding, noise, or slippage.
- High-Quality Diff Case Moulding — The differential case moulding is crafted to the highest standards, ensuring a reliable differential seal that prevents oil leakage and maintains optimal lubrication throughout your RC vehicle's drivetrain, critical for long-term reliability.
- Integrated Ring Gear and Diff Case Design — Rather than using separate components, this set features an integrated ring gear and diff case that work together as one strong unit, providing superior strength and eliminating potential failure points where separate components might separate under load.
- Factory Specification Replacement Part — This is the genuine ARRMA part that comes standard on qualifying models, ensuring perfect fitment and performance compatibility with your brushless RC truck or buggy without any modifications required.
Technical Performance
The ARRMA Differential Case Set 37T Main Gear represents precision engineering specifically designed for modern brushless RC vehicles. The 37T ring gear is a critical component in the final drive system of ARRMA's brushless BLX 3S models, controlling the speed and torque delivery to the wheels through carefully calculated gear ratios. The integrated design combines the ring gear and differential case into one moulded component, eliminating assembly points and potential failure modes while reducing overall weight. This composite construction provides the optimal balance between durability and lightweight performance—critical factors for maintaining speed and acceleration in competitive RC racing. The differential itself allows the wheels to rotate at different speeds during cornering whilst still receiving drive, which is essential for smooth handling and tyre wear management. The precision-manufactured tooth profile ensures engagement with the pinion gear is smooth and efficient, reducing noise and vibration that would otherwise rob your RC car of performance and indicate wear or damage. This component is designed to work seamlessly with ARRMA's brushless motor systems and electronic speed controllers, handling the high-frequency switching and power delivery characteristics of modern LiPo battery-powered RC vehicles. The tight moulding tolerances ensure a reliable seal that maintains proper differential oil levels, preventing the internal gears from running dry or overheating during extended driving sessions.
What's in the Box
- 1 x Ring Gear with Integrated Diff Case
- 1 x Diff Case Cap
What You Need to Complete
- Differential Pinion Shaft Assembly #ARA311031 (required to complete installation)
Compatible ARRMA Models
This differential case set is engineered as a direct replacement for numerous ARRMA brushless RC models including the 1/10 BIG ROCK 223S and 3S variants, 1/10 GRANITE 223S, 3S and brushed models, 1/10 GRANITE BOOST 2WD, 1/10 GRANITE MEGA 665, 1/10 SENTON 223S, 3S and brushed models, 1/10 SENTON BOOST 2WD, 1/10 VORTEKS 223S and brushed models, 1/10 VORTEKS BOOST 2WD, 1/8 INFRACTION 223S and 3S variants, 1/8 MOJAVE 4S, 1/8 TYPHON 223S and brushed models, 1/8 TYPHON MEGA 665, 1/8 VENDETTA 3S, and the high-speed 4S variants of KRATON and OUTCAST. Whether you're running 2WD or 4WD configurations, monster trucks, stadium trucks, short course trucks, or buggies, ARRMA has engineered this differential case to deliver the correct performance characteristics for each model's intended use.
Frequently Asked Questions
- Is this differential case compatible with my ARRMA RC model? — This 37T main gear differential case set is compatible with a wide range of ARRMA BLX 3S brushless models including monster trucks, short course trucks, stadium trucks, and buggies in both 1/10 and 1/8 scales. We recommend checking the detailed compatibility list provided by the manufacturer or contacting our team at RC Model Shop to confirm your specific model matches before ordering, as ARRMA produces various differential configurations across their product range.
- What does the integrated ring gear and diff case design mean for durability? — The integrated design combines two critical components into a single moulded unit, which eliminates the assembly point where separate ring gears and diff cases can separate under extreme load or impact. This single-piece integration provides superior structural strength and longevity compared to multi-part designs, making it particularly valuable for aggressive bashing and high-speed racing where drivetrain components endure tremendous stress.
- Do I need to replace any other differential components when installing this set? — This set includes the ring gear with integrated diff case and the diff case cap, but you will need the differential pinion shaft assembly #ARA311031 to complete the installation. Depending on the condition of your drivetrain, you may also want to inspect the pinion gear and differential gears, but those are separate components that may not require replacement if your damage is isolated to the ring gear or case.
- What maintenance does the differential require after installation? — ARRMA differentials are sealed units designed to retain differential oil, which provides lubrication and allows the internal gears to rotate smoothly. Ensure the diff case cap is securely fastened to maintain the seal, and check differential oil level periodically during the break-in period. Always use genuine ARRMA differential fluid rather than general-purpose gear oil, as the viscosity is specially formulated for these precision differentials.
- Can this part be used as an upgrade on older ARRMA models? — The 37T main gear differential case is specifically engineered for ARRMA's BLX 3S brushless systems and certain brushed models. Installing it on models not listed in the compatibility chart may result in incorrect gear ratios, poor handling balance, or drivetrain binding. Always verify compatibility before purchasing to ensure proper fitment and performance.
- How do I know if my differential case needs replacement? — Signs that your differential case may be damaged include grinding noises from the drivetrain, visible cracks in the composite case, oil leakage from around the differential, unequal wheel speed during cornering, or steering pull to one side despite proper suspension setup. If you notice any of these symptoms in your RC car UK racing or bashing sessions, a differential case replacement may be necessary.
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 ARRMA Differential Case Set 37T Main Gear: BLX 3S Z-AR310872 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.
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