JWL 39T Full Metal Front/Rear Differential with 13T Input Spiral Gear for ARRMA 8S Series
SKU JCS83912T
Review fitment and specifications below, then purchase this JWL upgrade through Amazon.
Purchases are completed securely on Amazon.
Specifications and fitment
Product details
Material Specifications
- Main gear: 39T with 13T input pinion (spiral cut), chromium steel, precision CNC machined
- Differential housing: 7075-T6 aerospace grade aluminum alloy
- Outdrive cups: Hardened chromium steel
- Fasteners: High-strength alloy steel screws
- Supporting bearings: Matched outdrive bearings included
- Internal gears: Spiral cut for heavy-duty 8S applications
Core Advantages
- Built for 8S brutality: Chromium steel spiral gears withstand extreme torque from 1/5 scale 8S systems
- Superior mesh: Spiral cut reduces noise and increases tooth contact area
- Easy maintenance: Split housing design for quick oil changes and inspection
- Complete set: Includes input gear, bearings, housing, and screws ¨C fully assembled ready to install
- Drop-in fitment: Direct replacement for ARRMA 1/5 scale 8S differentials
Usage Notes
- Mandatory break-in: Run at low speed for 2-3 minutes before full 8S throttle
- Use 100K-500K cSt differential oil for 1/5 scale; re-lubricate every 8-12 heavy runs
- Frequently inspect for gear wear and screw loosening due to high vibration
- Ensure proper shim alignment to prevent premature failure
Compatible Vehicle Models
Fits ARRMA 1/5 8S BLX series (front or rear differential)
- ARRMA Kraton 8S BLX
- ARRMA Outcast 8S BLX
Fitment and product support
Confirm the fit before you hit it.
Compatibility is part of the product. Review the platform collection or contact JWL before ordering if your setup is unclear.