Upgrade your drivetrain with the Cobra Racing Spiral Cut (Helical) Differential Gear Set, engineered for Traxxas X-Maxx 8S / 6S and XRT. Made from hardened steel, this premium upgrade delivers smoother power transfer, increased durability, and quieter operation compared to traditional straight-cut gears. The 13T-42T gear ratio ensures optimal torque distribution, making it the perfect choice for high-performance bashing, racing, and extreme off-road adventures.
Key Features:
- Spiral Cut (Helical) Gear Design – Improves power transfer and reduces drivetrain noise.
- Hardened Steel Construction – Built for extreme durability and long-lasting performance.
- Full Front & Rear Kit – Includes all necessary components for a complete upgrade.
- High-Performance Rubber Sealed Bearings – Keeps out dirt and debris for smoother operation.
- Optimized Gear Ratio (13T-42T) – Delivers enhanced torque and acceleration.
Why Upgrade to a Helical Differential Gear Set?
Stock straight-cut gears are prone to higher friction, gear noise, and wear over time, especially under extreme loads. The Cobra Racing Spiral Cut Differential Gear Set uses angled (helical) teeth to ensure:
✅ Smoother power delivery – Reduces shock load and drivetrain stress.
✅ Quieter operation – Less gear whine compared to straight-cut gears.
✅ Improved durability – Hardened steel and optimized gear contact for longevity.
✅ Better traction and control – Enhanced torque transfer for more consistent performance.
Whether you’re running 6S or 8S power, this upgrade ensures your drivetrain can handle the high torque and extreme forces of high-speed bashing and aggressive off-road racing.
Compatible Models:
This spiral cut helical differential gear set fits the following Traxxas models:
- Traxxas X-Maxx 6S / 8S
- Traxxas XRT 8S
If your model shares the X-Maxx/XRT differential system, this upgrade may be compatible.
Package Includes:
- Front & Rear Spiral Cut Differential Top Gears
- 2x Output spiral cut Gears (Front & Rear)
- High-Performance Rubber Sealed Bearings

Verified owner Wilfredo Acosta (verified owner) –
These diffs are well made great quality would buy again.
Verified owner Konrad (verified owner) –
Sweet set. Arrived as described. Shipped quickly for this era anyways. Well made parts. Rc runs alot quieter with the helical gears. This is the second set I have purchased and when I need others. I will be back